WO2022068218A1

WO2022068218A1 - Method and device for checking mems acceleration sensor chip

Info

Publication number: WO2022068218A1
Application number: PCT/CN2021/094562
Authority: WO
Inventors: 刘婧; 冯方方; 李宗伟; 杨长春; 周永健
Original assignee: 中国科学院地质与地球物理研究所
Priority date: 2021-04-26
Filing date: 2021-05-19
Publication date: 2022-04-07
Also published as: CN113203939A; CN113203939B; JP7221453B2; AU2021206818B1; JP2022554028A

Abstract

A method and apparatus for checking a MEMS acceleration sensor chip, the method comprising: applying a variable direct current voltage and an alternating current voltage of a preset frequency to a first electrode plate and a second electrode plate of a MEMS acceleration sensor chip to obtain a base capacitance value and a voltage-applied capacitance value between the first electrode plate and the second electrode plate (101, 102); on the basis of the obtained base capacitance value and the voltage-applied capacitance value, determining a breakover voltage, a capacitance change value, and a C-V characteristic curve (103); and on the basis of the base capacitance value, the breakover voltage, the capacitance change value, and the C-V characteristic curve of the first electrode plate and the second electrode plate, determining whether the MEMS acceleration sensor chip is normal (104). The invention is used to solve the existing technical problem that when a MEMS acceleration sensor chip has finished being processed, it cannot be preliminarily determined whether the MEMS acceleration sensor chip is normal, thus achieving checking of MEMS acceleration sensor chips after completion of processing, greatly saving costs.

Description

一种MEMS加速度传感器芯片的检测方法及装置A MEMS acceleration sensor chip detection method and device

技术领域technical field

本申请涉及传感器性能分析技术领域，尤其涉及一种MEMS加速度传感器芯片的检测方法及装置。The present application relates to the technical field of sensor performance analysis, and in particular, to a detection method and device for a MEMS acceleration sensor chip.

背景技术Background technique

微机电***(Micro Electro Mechanical Systems，MEMS)利用微纳米加工技术，在硅片上实现微型机械结构，大幅缩减了器件体积、降低了能耗并提高了可靠性。由于采用硅微加工技术和半导体集成电路工艺，易于实现批量生产，成本低。MEMS因其微型化、可集成、成本低、功耗低等优点广泛应用在消费电子、汽车电子、生物医疗等领域，MEMS加速度传感器便是其中一种。Micro Electro Mechanical Systems (MEMS) utilizes micro-nano processing technology to realize micro-mechanical structures on silicon wafers, which greatly reduces the size of devices, reduces energy consumption and improves reliability. Due to the adoption of silicon micromachining technology and semiconductor integrated circuit technology, mass production is easy to achieve and the cost is low. MEMS are widely used in consumer electronics, automotive electronics, biomedical and other fields because of their advantages of miniaturization, integration, low cost, and low power consumption. MEMS acceleration sensor is one of them.

MEMS加速度传感器芯片在设计、加工完成后，需要对其性能进行测试分析，以确定其是否满足设计要求、能否正常工作。由于MEMS芯片封装成本往往占整个MEMS加速度传感器元件成本的70～80％。因此，在MEMS加速度传感器芯片加工完成后对MEMS加速度传感器芯片性能进行初步测试，排除不能正常工作的芯片，筛选出性能良好的MEMS加速度传感器芯片进行封装，成为目前亟待解决的问题。After the MEMS acceleration sensor chip is designed and processed, its performance needs to be tested and analyzed to determine whether it meets the design requirements and can work normally. Because the cost of MEMS chip packaging often accounts for 70-80% of the cost of the entire MEMS acceleration sensor element. Therefore, preliminarily testing the performance of the MEMS acceleration sensor chip after the processing of the MEMS acceleration sensor chip, excluding the chips that cannot work normally, and screening out the MEMS acceleration sensor chip with good performance for packaging, has become an urgent problem to be solved at present.

发明内容SUMMARY OF THE INVENTION

本申请实施例提供了一种MEMS加速度传感器芯片的检测方法及装置，用以解决现有的MEMS加速度传感器芯片在加工完成后，不能初步排除非正常工作的MEMS加速度传感器芯片而导致成本高的技术问题。The embodiments of the present application provide a detection method and device for a MEMS acceleration sensor chip, which are used to solve the problem that the existing MEMS acceleration sensor chip cannot be preliminarily excluded after the processing of the MEMS acceleration sensor chip is completed, resulting in high cost technology. question.

一方面，本申请实施例提供了一种MEMS加速度传感器芯片的检测方法，其特征在于，方法包括：将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使第二极板朝着第一极板的方向移动；其中，第一极板是固定极板，第二极板是可动极板；将预设频率的交流电压加在第一极板与第二极板，以获得第一极板与第二极板之间的基础电容值和加压电容值；其中，基础电容值为直流电压的电压值为零时，第一极板与第二极板之间的电容值，加压电容值为直流电压的电压值不为零时，第一极板与第二极板之间的电容值；基于获得的第一极板与第二极板之间的基础电容值和加压电容值，确定MEMS加速度传感器芯片第一极板与第二极板之间的电压-电容特性曲线、转折电压以及电容变化值；根据第一极板与第二极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线，判断MEMS加速度传感器芯片是否正常。On the one hand, an embodiment of the present application provides a method for detecting a MEMS acceleration sensor chip, characterized in that the method includes: applying a variable DC voltage to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, so that the The second pole plate moves in the direction of the first pole plate; wherein, the first pole plate is a fixed pole plate, and the second pole plate is a movable pole plate; the AC voltage of the preset frequency is applied to the first pole plate and the second pole plate. Diode plate, to obtain the basic capacitance value and the pressure capacitance value between the first electrode plate and the second electrode plate; wherein, when the basic capacitance value is zero, the voltage value of the DC voltage is zero, the first electrode plate and the second electrode plate The capacitance value between the plates, the pressure capacitance value when the voltage value of the DC voltage is not zero, the capacitance value between the first plate and the second plate; based on the obtained first plate and the second plate The basic capacitance value and the pressure capacitance value between the MEMS acceleration sensor chips determine the voltage-capacitance characteristic curve, the turning voltage and the capacitance change value between the first plate and the second plate of the MEMS acceleration sensor chip; according to the first plate and the second plate The basic capacitance value between the plates, the turning voltage, the capacitance change value and the voltage-capacitance characteristic curve are used to judge whether the MEMS acceleration sensor chip is normal.

本申请实施例提供的一种MEMS加速度传感器芯片的检测方法，通过测量不同直流电压值下两极板间的电容值得到MEMS加速度传感器芯片的基础电容值、转折电压、电容变化值。通过得到的基础电容值、转折电压、电容变化值分析MEMS加速度传感器在加工过程中是否存在问题，以及确定存在哪些操作或工艺方面的问题，以便后续改进。An embodiment of the present application provides a detection method for a MEMS acceleration sensor chip. The basic capacitance value, turning voltage, and capacitance change value of the MEMS acceleration sensor chip are obtained by measuring the capacitance value between two polar plates under different DC voltage values. Through the obtained basic capacitance value, turning voltage, and capacitance change value, analyze whether there are problems in the processing of the MEMS acceleration sensor, and determine which operation or process problems exist for subsequent improvement.

在本申请的一种实现方式中，方法还包括：确定MEMS加速度传感器芯片第二极板与第三极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线；将MEMS加速度传感器芯片第二极板与第三极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线与MEMS加速度传感器芯片第二极板与第三极板之间对应的基础电容值、转折电压、电容变化值以及电压-电容特性曲线的理论设计值进行对比，判断MEMS加速度传感器芯片是否正常。In an implementation manner of the present application, the method further includes: determining a basic capacitance value, a turning voltage, a capacitance change value, and a voltage-capacitance characteristic curve between the second plate and the third plate of the MEMS acceleration sensor chip; The basic capacitance value, turning voltage, capacitance change value, and voltage-capacitance characteristic curve between the second plate and the third plate of the acceleration sensor chip and the basis for the correspondence between the second plate and the third plate of the MEMS acceleration sensor chip The capacitance value, turning voltage, capacitance change value and the theoretical design value of the voltage-capacitance characteristic curve are compared to judge whether the MEMS acceleration sensor chip is normal.

在本申请的一种实现方式中，将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使第二极板朝着第一极板的方向移动，具体包括：将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板；基于预设的步进电压值，调整直流电压值，以使第二极板朝着第一极板的方向移动；其中，第二极板的移动距离由当前直流电压值决定。In an implementation manner of the present application, a variable DC voltage is applied to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, so that the second electrode plate moves in the direction of the first electrode plate, which specifically includes : apply a variable DC voltage to the first and second polar plates of the MEMS acceleration sensor chip; adjust the DC voltage value based on the preset step voltage value so that the second polar plate faces the first polar plate The direction of movement; wherein, the moving distance of the second plate is determined by the current DC voltage value.

在本申请的一种实现方式中，基于预设的步进电压值，调整直流电压的输出电压值，以使第二极板朝着第一极板的方向移动，具体包括：基于预设的步进电压值调整直流电压值，以使第一极板与第二极板之间获得不同的直流电压值，以基于不同的直流电压值在第一极板与第二极板之间产生不同大小的静电力，用以克服基于第二极板移动引起弹性梁形变，所产生的弹性力；其中，弹性梁为连接在MEMS加速度传感器芯片第二极板上的组件。In an implementation manner of the present application, adjusting the output voltage value of the DC voltage based on a preset step voltage value, so that the second pole plate moves in the direction of the first pole plate, specifically includes: based on the preset step voltage value Stepping the voltage value to adjust the DC voltage value so that different DC voltage values are obtained between the first electrode plate and the second electrode plate, so as to generate differences between the first electrode plate and the second electrode plate based on the different DC voltage values The electrostatic force is used to overcome the elastic force generated by the deformation of the elastic beam caused by the movement of the second electrode plate; wherein, the elastic beam is a component connected to the second electrode plate of the MEMS acceleration sensor chip.

在本申请的一种实现方式中，将预设频率的交流电压加在第一极板与第二极板，以获得第一极板与的第二极板之间的基础电容值和加压电容值，具体包括：将预设频率的交流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使第一极板与第二极板之间产生电流；基于所产生的电流信息，计算第一极板与第二极板之间的基础电容值和加压电容值；其中，电流信息包括电流的幅值及相位。In an implementation manner of the present application, an AC voltage of a preset frequency is applied to the first electrode plate and the second electrode plate to obtain the basic capacitance value and the voltage between the first electrode plate and the second electrode plate. The capacitance value specifically includes: applying an AC voltage of a preset frequency to the first plate and the second plate of the MEMS acceleration sensor chip, so that a current is generated between the first plate and the second plate; based on the generated The current information is used to calculate the basic capacitance value and the pressurized capacitance value between the first electrode plate and the second electrode plate; wherein, the current information includes the amplitude and phase of the current.

在本申请的一种实现方式中，转折电压为公式

结果等于零的情况，V所对应的电压值；其中，ε为第一极板与第二极板间介质的介电常数，A为第一极板与第二极板的极板面积，V为加在第一极板与第二极板之间的直流电压值，d为第一极板与第二极板的极板间距，k为弹性梁的弹性系数。 In an implementation manner of the present application, the breakover voltage is the formula

When the result is equal to zero, the voltage value corresponding to V; among them, ε is the dielectric constant of the medium between the first plate and the second plate, A is the plate area of the first plate and the second plate, and V is The DC voltage value applied between the first pole plate and the second pole plate, d is the pole plate distance between the first pole plate and the second pole plate, and k is the elastic coefficient of the elastic beam.

在本申请的一种实现方式中，根据第一极板与第二极板的基础电容值、转折电压以及电容变化值，判断MEMS加速度传感器芯片是否正常，具体包括：将当前MEMS加速度传感器芯片第一极板与第二极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线，与MEMS加速度传感器芯片第一极板与第二极板之间对应的基础电容值、转折电压、电容变化值以及电压-电容特性曲线的理论设计值，进行对比；在当前基础电容值、转折电压、电容变化值以及电压-电容特性曲线中的任意一项或多项，与对应的基础电容值、转折电压、电容变化值以及电压-电容特性曲线的理论设计值的差值大于预设阈值的情况下，确定MEMS加速度传感器芯片不正常。In an implementation manner of the present application, judging whether the MEMS acceleration sensor chip is normal according to the basic capacitance value, the turning voltage and the capacitance change value of the first electrode plate and the second electrode plate specifically includes: The basic capacitance value, turning voltage, capacitance change value and voltage-capacitance characteristic curve between one electrode plate and the second electrode plate, and the corresponding basic capacitance value between the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, Turning voltage, capacitance change value and theoretical design value of the voltage-capacitance characteristic curve are compared; any one or more of the current basic capacitance value, turning voltage, capacitance change value and voltage-capacitance characteristic curve are compared with the corresponding When the difference between the basic capacitance value, the turning voltage, the capacitance change value, and the theoretical design value of the voltage-capacitance characteristic curve is greater than the preset threshold, it is determined that the MEMS acceleration sensor chip is abnormal.

在本申请的一种实现方式中，在直流电压值不为零时，交流电压峰值绝对值的预设倍数小于直流电压值的绝对值。In an implementation manner of the present application, when the DC voltage value is not zero, the preset multiple of the absolute value of the peak value of the AC voltage is smaller than the absolute value of the DC voltage value.

在本申请的一种实现方式中，在将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使第二极板朝着第一极板的方向移动之前，方法还包括：在MEMS加速度传感器芯片的第一极板的第一表面的边缘设置第一限位凸点，以及在第三极板的第一表面的边缘设置第二限位凸点，用以避免在直流电压作用下使得第二极板移动过程中与第一极板或者第三极板接触。In an implementation manner of the present application, before applying a variable DC voltage to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip to move the second electrode plate toward the direction of the first electrode plate, The method further includes: arranging a first limit bump on the edge of the first surface of the first plate of the MEMS acceleration sensor chip, and disposing a second limit bump on the edge of the first surface of the third plate, to Avoid contacting the second electrode plate with the first electrode plate or the third electrode plate during the movement of the second electrode plate under the action of the DC voltage.

另一方面，本申请实施例还提供了一种MEMS加速度传感器芯片的检测装置，其特征在于，装置包括：电压输出模块，用于将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使第二极板朝着第一极板的方向移动；其中，第一极板是固定极板，第二极板是可动极板；电压输出模块，还用于将预设频率的交流电压加在第一极板与第二极板，以获得第一极板与第二极板之间的基础电容值和加压电容值；其中，基础电容值为直流电压的电压值为零时，第一极板与第二极板之间的电容值，加压电容值为直流电压的电压值不为零时，第一极板与第二极板之间的电容值；确定模块，用于基于获得的第一极板与第二极板之间的基础电容值和加压电容值，确定MEMS加速度传感器芯片第一极板与第二极板之间的电压-电容特性曲线、转折电压以及电容变化值；判断模块用于，根据第一极板与第二极板的基础电容值、转折电压、电容变化值以及电压-电容特性曲线，判断MEMS加速度传感器芯片是否正常。On the other hand, an embodiment of the present application also provides a detection device for a MEMS acceleration sensor chip, characterized in that the device includes: a voltage output module for applying a variable DC voltage to the first plate of the MEMS acceleration sensor chip and the second pole plate, so that the second pole plate moves in the direction of the first pole plate; wherein, the first pole plate is a fixed pole plate, and the second pole plate is a movable pole plate; the voltage output module is also used for The AC voltage of the preset frequency is added to the first pole plate and the second pole plate to obtain the basic capacitance value and the pressurized capacitance value between the first pole plate and the second pole plate; wherein, the basic capacitance value is a DC voltage When the voltage value is zero, the capacitance value between the first electrode plate and the second electrode plate, and the voltage value of the pressure capacitor value are not zero when the voltage value of the DC voltage is not zero, the capacitance value between the first electrode plate and the second electrode plate value; a determination module for determining the voltage between the first plate and the second plate of the MEMS acceleration sensor chip based on the obtained basic capacitance value and the pressure capacitance value between the first plate and the second plate- Capacitance characteristic curve, turning voltage and capacitance change value; the judgment module is used to judge whether the MEMS acceleration sensor chip is based on the basic capacitance value, turning voltage, capacitance change value and voltage-capacitance characteristic curve of the first electrode plate and the second electrode plate normal.

附图说明Description of drawings

此处所说明的附图用来提供对本申请的进一步理解，构成本申请的一部分，本申请的示意性实施例及其说明用于解释本申请，并不构成对本申请的不当限定。在附图中：The drawings described herein are used to provide further understanding of the present application and constitute a part of the present application. The schematic embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation of the present application. In the attached image:

图1为本申请实施例提供的一种MEMS加速度传感器芯片简易结构示意图；1 is a schematic diagram of a simple structure of a MEMS acceleration sensor chip provided by an embodiment of the application;

图2为本申请实施例提供的一种MEMS加速度传感器芯片的检测方法流程图；2 is a flowchart of a method for detecting a MEMS acceleration sensor chip provided by an embodiment of the present application;

图3为本申请实施例提供的一种MEMS加速度传感器芯片在直流电压下的位移方向示意图；3 is a schematic diagram of a displacement direction of a MEMS acceleration sensor chip under a DC voltage provided by an embodiment of the present application;

图4为本申请实施例提供的一种MEMS加速度传感器芯片的物理模型示意图；4 is a schematic diagram of a physical model of a MEMS acceleration sensor chip provided by an embodiment of the present application;

图5为本申请实施例提供的一种MEMS加速度传感器芯片的电容与电压特性曲线示意图；5 is a schematic diagram of a capacitance-voltage characteristic curve of a MEMS acceleration sensor chip provided by an embodiment of the application;

图6为本申请实施例提供的一种MEMS加速度传感器芯片的限位凸点位置结构示意图；6 is a schematic structural diagram of a position limit bump of a MEMS acceleration sensor chip according to an embodiment of the present application;

图7为本申请实施例提供的一种MEMS加速度传感器芯片的检测装置结构示意图。FIG. 7 is a schematic structural diagram of a detection device for a MEMS acceleration sensor chip according to an embodiment of the present application.

具体实施方式Detailed ways

为使本申请的目的、技术方案和优点更加清楚，下面将结合本申请具体实施例及相应的附图对本申请技术方案进行清楚、完整地描述。显然，所描述的实施例仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be clearly and completely described below with reference to the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

图1为本申请实施例提供的一种MEMS加速度传感器芯片简易结构示意图，MEMS加速度传感器芯片由第一极板、第二极板、第三极板三个极板构成。其中，第一极板与第三极板是固定极板，在外力作用下不会产生运动。第二极板位于第一极板与第三极板的中间位置，第二极板是可动的，在本申请实施例中也称第二极板为可动极板。第二极板的第一表面与第一极板的第一表面形成了一个上下极板面积相等的平板电容器，第二极板的第二表面与第三极板的第一表面同样形成了一个上下极板面积相等的平板电容器。其中，第二极板的第一表面与第一极板的第一表面相对设置，以使所述第二极板与第一极板形成第一电容；第二极板的第二表面与第三极板的第一表面相对设置，以使所述第二极板与第三极板形成第二电容。FIG. 1 is a schematic diagram of a simple structure of a MEMS acceleration sensor chip provided by an embodiment of the present application. The MEMS acceleration sensor chip is composed of three polar plates: a first electrode plate, a second electrode plate, and a third electrode plate. Among them, the first pole plate and the third pole plate are fixed pole plates, and will not move under the action of external force. The second pole plate is located in the middle of the first pole plate and the third pole plate, the second pole plate is movable, and is also referred to as a movable pole plate in the embodiment of the present application. The first surface of the second electrode plate and the first surface of the first electrode plate form a plate capacitor with the same area of the upper and lower electrode plates, and the second surface of the second electrode plate and the first surface of the third electrode plate also form a Plate capacitors with equal upper and lower plate areas. Wherein, the first surface of the second electrode plate is opposite to the first surface of the first electrode plate, so that the second electrode plate and the first electrode plate form a first capacitor; The first surfaces of the triode plates are arranged opposite to each other, so that the second electrode plate and the third electrode plate form a second capacitor.

本申请实施例提供的一种MEMS加速度传感器芯片的检测方法及装置，通过测量不同电压下两极板间的电容值得到MEMS加速度传感器芯片的基础电容值、转折电压、电容变化值。如果实测值与相应的理论设计值的误差在合理范围内，则该MEMS加速度传感器芯片符合设计要求。否则，可以根据其基础电容值、转折电压、电容变化值以及电压-电容特性曲线分析MEMS加速度传感器加工过程中在操作或工艺方面存在哪些问题，以便后续改进。The embodiments of the present application provide a method and device for detecting a MEMS acceleration sensor chip. The basic capacitance value, turning voltage, and capacitance change value of the MEMS acceleration sensor chip are obtained by measuring the capacitance value between two polar plates under different voltages. If the error between the measured value and the corresponding theoretical design value is within a reasonable range, the MEMS acceleration sensor chip meets the design requirements. Otherwise, it is possible to analyze what problems exist in operation or technology during the processing of the MEMS acceleration sensor according to its basic capacitance value, turning voltage, capacitance change value, and voltage-capacitance characteristic curve, so as to facilitate subsequent improvement.

下面继续详细的说明。The detailed description continues below.

图2为本申请实施例提供的一种MEMS加速度传感器芯片的检测方法流程图。FIG. 2 is a flowchart of a detection method of a MEMS acceleration sensor chip provided by an embodiment of the present application.

如图2所示，本申请实施例提供的一种MEMS加速度传感器芯片的检测方法具体包括以下步骤：As shown in FIG. 2 , a method for detecting a MEMS acceleration sensor chip provided by an embodiment of the present application specifically includes the following steps:

步骤101、将可变直流电压的正极和负极分别加在MEMS加速度传感器芯片的第一极板与第二极板，以使第二极板朝着第一极板的方向移动。其中，可变直流电压是电压值可调节的直流电压，即具有不同电压值的直流电压。 Step 101 , adding the positive and negative electrodes of the variable DC voltage to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip respectively, so that the second electrode plate moves toward the direction of the first electrode plate. The variable DC voltage is a DC voltage whose voltage value can be adjusted, that is, a DC voltage with different voltage values.

由于MEMS加速度传感器芯片第二极板的第一表面与第一极板的第一表面(即第一极板与第二极板相对的两个表面)形成了一个面积相等的平板电容器。因此，由公式

得知，第二极板的第一表面与第一极板的第一表面形成的平板电容器的电容值；其中，C为第一极板与第二极板间的电容量，ε为第一极板与第二极板间的介电常数，A为第一极板与第二极板的极板面积，d为第一极板与第二极板的极板间距。 Because the first surface of the second electrode plate of the MEMS acceleration sensor chip and the first surface of the first electrode plate (that is, two surfaces opposite to the first electrode plate and the second electrode plate) form a plate capacitor with the same area. Therefore, by the formula

It is known that the capacitance value of the plate capacitor formed by the first surface of the second pole plate and the first surface of the first pole plate; wherein, C is the capacitance between the first pole plate and the second pole plate, and ε is the first pole plate. The dielectric constant between the electrode plate and the second electrode plate, A is the electrode plate area of the first electrode plate and the second electrode plate, and d is the electrode plate distance between the first electrode plate and the second electrode plate.

为获得MEMS加速度传感器芯片的基础电容值、转折电压、电容变化值，首先需要将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板。In order to obtain the basic capacitance value, turning voltage, and capacitance change value of the MEMS acceleration sensor chip, it is first necessary to apply a variable DC voltage to the first plate and the second plate of the MEMS acceleration sensor chip.

需要说明的是，在将直流电压加在MEMS加速度传感器芯片的第一极板与第二极板时，可以将直流电压的正极接在MEMS加速度传感器芯片的第一极板，将直流电压的负极接在MEMS加速度传感器芯片的第二极板；也可以将直流电压的负极接在MEMS加速度传感器芯片的第一极板，将直流电压的正极接在MEMS加速度传感器芯片的第二极板。It should be noted that when the DC voltage is applied to the first plate and the second plate of the MEMS acceleration sensor chip, the positive pole of the DC voltage can be connected to the first plate of the MEMS acceleration sensor chip, and the negative pole of the DC voltage can be connected to the first plate of the MEMS acceleration sensor chip. It is connected to the second plate of the MEMS acceleration sensor chip; the negative electrode of the DC voltage can also be connected to the first plate of the MEMS acceleration sensor chip, and the positive electrode of the DC voltage can be connected to the second plate of the MEMS acceleration sensor chip.

在将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板之后，基于预设的步进电压值，调整直流电压值，以使第二极板朝着第一极板的方向移动。After the variable DC voltage is applied to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, the DC voltage value is adjusted based on the preset step voltage value, so that the second electrode plate faces the first electrode plate move in the direction.

具体地，基于预设的步进电压值，调整直流电压的输出电压。其中，预设的步进电压值为每次调整直流电压值时，对直流电压的输出改变值。例如，预设的步进电压值为1V，在每次调整直流电压值时，均使直流电压值增加1V或者减小1V。在MEMS加速度传感器芯片的第一极板与第二极板获得电压后(即加在MEMS加速度传感器芯片的第一极板与第二极板上的电压不为零后)，第一极板和第二极板得到充电。Specifically, the output voltage of the DC voltage is adjusted based on a preset step voltage value. Wherein, the preset step voltage value is the value of the output change of the DC voltage each time the DC voltage value is adjusted. For example, the preset step voltage value is 1V, and each time the DC voltage value is adjusted, the DC voltage value is increased by 1V or decreased by 1V. After the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip obtain a voltage (that is, after the voltage applied to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip is not zero), the first electrode plate and the second electrode plate are not zero. The second plate is charged.

需要说明的是，如果直流电压的正极接在MEMS加速度传感器芯片的第一极板，直流电压的负极接在MEMS加速度传感器芯片的第二极板，则第一极板的第一表面充满正电荷，第二极板的第一表面充满负电荷；如果直流电压的负极接在MEMS加速度传感器芯片的第一极板，直流电压的正极接在MEMS加速度传感器芯片的第二极板，则第一极板的第一表面充满负电荷，第二极板的第一表面充满正电荷。It should be noted that if the positive pole of the DC voltage is connected to the first plate of the MEMS acceleration sensor chip, and the negative pole of the DC voltage is connected to the second plate of the MEMS acceleration sensor chip, the first surface of the first plate is full of positive charges. , the first surface of the second electrode plate is full of negative charges; if the negative electrode of the DC voltage is connected to the first electrode plate of the MEMS acceleration sensor chip, and the positive electrode of the DC voltage is connected to the second electrode plate of the MEMS acceleration sensor chip, the first electrode The first surface of the plate is full of negative charges, and the first surface of the second plate is full of positive charges.

由于第一极板是固定极板，第二极板是移动极板，因此，不论是第一极板的第一表面充满正电荷，第二极板的第一表面充满负电荷，还是第一极板的第一表面充满负电荷，第二极板的第一表面充满正电荷，第二极板均会由于极板间产生的相互吸引的静电力，从而使第二极板有朝着第一极板方向运动的趋势。Since the first electrode plate is a fixed electrode plate and the second electrode plate is a moving electrode plate, whether the first surface of the first electrode plate is full of positive charges, the first surface of the second electrode plate is full of negative charges, or the first The first surface of the pole plate is full of negative charges, and the first surface of the second pole plate is full of positive charges, and the second pole plate will be due to the electrostatic force of mutual attraction between the pole plates, so that the second pole plate has a tendency to move towards the first pole. A trend of movement in the direction of the plate.

图3为本申请实施例提供的一种MEMS加速度传感器芯片在直流电压下的位移方向示意图。FIG. 3 is a schematic diagram of a displacement direction of a MEMS acceleration sensor chip under a DC voltage according to an embodiment of the present application.

如图3所示，在第一极板与第二极板间加上电压值大小为V的电压后，第二极板朝向第一极板移动。另外，由于第一极板与第三极板均为固定极板，假设在第一极板与第二极板所加的电压值为零的情况下，第一极板与第二极板以及第二极板与第三极板之间的距离均为d ₀，在第二极板朝向第一极板移动x的情况下，第一极板与第二极板的极板间距为d ₀-x，第二极板与第三极板的极板间距为d ₀+x。 As shown in FIG. 3 , after a voltage with a voltage value of V is applied between the first electrode plate and the second electrode plate, the second electrode plate moves toward the first electrode plate. In addition, since the first electrode plate and the third electrode plate are both fixed electrode plates, it is assumed that the first electrode plate and the second electrode plate and the The distance between the second pole plate and the third pole plate is d ₀ . When the second pole plate moves x toward the first pole plate, the distance between the first pole plate and the second pole plate is d ₀ -x, the distance between the second pole plate and the third pole plate is d ₀ +x.

图4为本申请实施例提供的一种MEMS加速度传感器芯片的物理模型示意图。MEMS加速度传感器由质量块、弹性梁和固定框架组成。固定框架的上表面等效为第一极板或者第三极板，质量块等效为第二极板，固定框架的下表面等效为第三极板或者第一极板。质量块通过弹性梁连接到框架中。当质量块发生运动时，会使连接到质量块的弹性梁产生形变，由此产生弹性力，可以等效为一个弹簧结构。FIG. 4 is a schematic diagram of a physical model of a MEMS acceleration sensor chip provided by an embodiment of the present application. The MEMS acceleration sensor consists of a mass block, an elastic beam and a fixed frame. The upper surface of the fixed frame is equivalent to the first pole plate or the third pole plate, the mass block is equivalent to the second pole plate, and the lower surface of the fixed frame is equivalent to the third pole plate or the first pole plate. The mass is connected to the frame by elastic beams. When the mass block moves, it will deform the elastic beam connected to the mass block, thereby generating elastic force, which can be equivalent to a spring structure.

第一极板与第二极板之间产生的静电力，会使第二极板克服弹性梁应变产生的弹性力，并使第二极板最终停在弹性力与极板间静电力相等的位置。The electrostatic force generated between the first pole plate and the second pole plate will make the second pole plate overcome the elastic force generated by the elastic beam strain, and make the second pole plate finally stop at the point where the elastic force and the electrostatic force between the pole plates are equal. Location.

其中，第一极板与第二极板之间的静电力为

弹性梁发生形变产生的弹力为F＝kx。其中，d ₀为第一极板与第二极板之间所加电压的电压值为零时，第一极板与第二极板距离；x为第二极板朝着第一极板运动的距离；V为加在第一极板与第二极板之间的直流电压值；k为弹性梁的弹性系数。 Among them, the electrostatic force between the first pole plate and the second pole plate is

The elastic force generated by the deformation of the elastic beam is F=kx. Wherein, d ₀ is the distance between the first pole plate and the second pole plate when the voltage value of the applied voltage between the first pole plate and the second pole plate is zero; x is the movement of the second pole plate towards the first pole plate distance; V is the DC voltage value added between the first pole plate and the second pole plate; k is the elastic coefficient of the elastic beam.

在本申请的一个实施例中，还可以通过上述步骤101提供的方法将可变直流电压加在MEMS加速度传感器芯片的第二极板与第三极板，以使第二极板朝着第三极板的方向移动。In an embodiment of the present application, a variable DC voltage can also be applied to the second electrode plate and the third electrode plate of the MEMS acceleration sensor chip by the method provided in the above step 101, so that the second electrode plate faces the third electrode plate. The direction of the plate moves.

步骤102、将预设频率的交流电压的正极和负极分别加在第一极板与第二极板，以获得第一极板与第二极板之间的基础电容值和加压电容值。Step 102: Add the positive and negative electrodes of the AC voltage of the preset frequency to the first electrode plate and the second electrode plate, respectively, to obtain the basic capacitance value and the pressurized capacitance value between the first electrode plate and the second electrode plate.

在将直流电压加在MEMS加速度传感器芯片的第一极板与第二极板后，本申请实施例还将预设频率的交流电压加在第一极板与第二极板。通过预设频率的交流电压，测量MEMS加速度传感器芯片第一极板与第二极板在不同直流电压值下的电容值。After the DC voltage is applied to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, the embodiment of the present application also applies an AC voltage of a preset frequency to the first electrode plate and the second electrode plate. The capacitance values of the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip under different DC voltage values are measured by an AC voltage with a preset frequency.

具体地，在直流电压的电压值为零时，将预设频率的交流电压的两输出端分别加在MEMS加速度传感器芯片的第一极板与第二极板，以使第一极板与第二极板之间产生电流，基于所产生的电流信息，计算第一极板与第二极板之间的基础电容值；其中，所述电流信息包括电流的幅值及相位。Specifically, when the voltage value of the DC voltage is zero, the two output ends of the AC voltage of the preset frequency are respectively applied to the first plate and the second plate of the MEMS acceleration sensor chip, so that the first plate and the second plate are respectively applied. A current is generated between the two electrode plates, and based on the generated current information, the basic capacitance value between the first electrode plate and the second electrode plate is calculated; wherein, the current information includes the amplitude and phase of the current.

在本申请的一个实施例中，电容值的具体计算原理如下：In an embodiment of the present application, the specific calculation principle of the capacitance value is as follows:

第一极板与第二极板之间的阻抗

其中，Z的模值和辐角分别为：

即R＝|Z|cosθ _Z,X＝|Z|cosθ _Z。 Impedance between first plate and second plate

where the modulus and argument of Z are:

That is, R=|Z|cosθ _Z , X=|Z|cosθ _Z .

在本申请的一个实施例中，基于预设的步进电压值，在每次改变直流电压值，并在第二极板稳定后，均通过预设频率的交流电压，测量一次MEMS加速度传感器芯片第一极板与第二极板在不同直流电压值下的加压电容值。需要说明的是，由于每次改变第一极板和第二极板间的直流电压值后，第二极板在静电力和弹性力作用下会产生一定距离的运动，从而引起第一极板与第二极板之间的距离发生变化，由公式

可知，第一极板与第二极板之间的电容随第一极板与第二极板之间的距离发生变化，因此，第一极板与第二极板在不同直流电压值下的加压电容值也会随之变化。 In an embodiment of the present application, based on the preset step voltage value, each time the DC voltage value is changed, and after the second plate is stabilized, the MEMS acceleration sensor chip is measured once by the AC voltage of the preset frequency The pressure capacitance value of the first electrode plate and the second electrode plate under different DC voltage values. It should be noted that, because the DC voltage value between the first pole plate and the second pole plate is changed every time, the second pole plate will move a certain distance under the action of electrostatic force and elastic force, thereby causing the first pole plate to move. The distance from the second plate changes, given by the formula

It can be seen that the capacitance between the first pole plate and the second pole plate changes with the distance between the first pole plate and the second pole plate. Therefore, the difference between the first pole plate and the second pole plate under different DC voltage values The boost capacitor value will also change accordingly.

还需要说明的是，在直流电压值不为零时，交流电压峰值绝对值的预设倍数小于直流电压值的绝对值；其中，预设倍数至少应该大于一百，即直流电压的电压值应该大于交流电压峰值两个数量级以上，从而避免交流电压过高而使第二极板的位置产生移动，而影响电容值测量结果的准确性。It should also be noted that when the DC voltage value is not zero, the preset multiple of the absolute value of the peak value of the AC voltage is less than the absolute value of the DC voltage value; wherein, the preset multiple should be at least greater than one hundred, that is, the voltage value of the DC voltage should be It is more than two orders of magnitude greater than the peak value of the AC voltage, so as to prevent the position of the second electrode plate from moving due to the high AC voltage, thereby affecting the accuracy of the capacitance value measurement result.

在本申请的一个实施例中，还可以通过上述步骤102提供的方法将预设频率的交流电压的正极和负极分别加在第二极板与第三极板，以获得第二极板与第三极板之间的基础电容值和加压电容值。In an embodiment of the present application, the positive electrode and the negative electrode of the AC voltage of the preset frequency can also be added to the second electrode plate and the third electrode plate respectively by the method provided in the above step 102, so as to obtain the second electrode plate and the third electrode plate. The base capacitance value and the boost capacitance value between the three-pole plates.

步骤103、基于获得的第一极板与第二极板之间的基础电容值和加压电容值，确定MEMS加速度传感器芯片第一极板与第二极板之间的转折电压及与电容变化值。 Step 103 , based on the obtained basic capacitance value and pressurized capacitance value between the first electrode plate and the second electrode plate, determine the inflection voltage between the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip and the change in capacitance. value.

在获得第一极板与第二极板之间的基础电容值和加压电容值之后，通过电压值与电容值的对应关系，绘制MEMS加速度传感器芯片第一极板与第二极板所对应的电压-电容特性曲线(C-V特性曲线)。After obtaining the basic capacitance value and the pressure capacitance value between the first electrode plate and the second electrode plate, through the corresponding relationship between the voltage value and the capacitance value, draw the corresponding relationship between the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip. The voltage-capacitance characteristic curve (C-V characteristic curve) of .

图5为本申请实施例提供的一种MEMS加速度传感器芯片的电容与电压特性曲线示意图。FIG. 5 is a schematic diagram of a capacitance-voltage characteristic curve of a MEMS acceleration sensor chip according to an embodiment of the present application.

如图5所示，直流电压值为0时，所对应的电容值为第一极板与第二极板之间的基础电容值。基于预设的步进电压值，调整后直流电压值所对应的电容值为第一极板与第二极板之间的加压电容值。需要说明的是，图5中电压所对应的正负半轴为直流电压的正极接在第一极板，负极接在第二极板，以及直流电压的负极接在第一极板，正极接在第二极板的两种情况。在本申请的一个实施例中，转折电压为极板间电容开始急速变化时，所对应的电压值，转折电压的具体计算原理如下：As shown in FIG. 5 , when the DC voltage value is 0, the corresponding capacitance value is the basic capacitance value between the first electrode plate and the second electrode plate. Based on the preset step voltage value, the capacitance value corresponding to the adjusted DC voltage value is the pressurized capacitance value between the first electrode plate and the second electrode plate. It should be noted that the positive and negative semi-axes corresponding to the voltage in FIG. 5 are that the positive pole of the DC voltage is connected to the first pole plate, the negative pole is connected to the second pole plate, and the negative pole of the DC voltage is connected to the first pole plate, and the positive pole is connected to the first pole plate. in both cases of the second plate. In an embodiment of the present application, the turning voltage is the corresponding voltage value when the capacitance between the plates begins to change rapidly. The specific calculation principle of the turning voltage is as follows:

第二极板所受的合力

因此

The resultant force on the second plate

therefore

当

时，

此时若第二极板位置发生轻微扰动，如产生δd的微小位移时，在第二极板上所产生的合力和位移是反方向的。因此，可以把第二极板重新拉回到平衡位置。而当

时，

此时若第二极板位置发生轻微扰动，如产生δd的微小位移时。在第二极板上所产生的合力和位移是同方向的，因此会进一步将第二极板拉离平衡位置，从而使极板间距急速变化，对应极板间电容也急速变化。 when

hour,

At this time, if a slight disturbance occurs in the position of the second pole plate, such as a slight displacement of δd, the resultant force and displacement generated on the second pole plate are in opposite directions. Therefore, the second plate can be pulled back to the equilibrium position. and when

hour,

At this time, if the position of the second plate is slightly disturbed, such as a slight displacement of δd. The resultant force and displacement generated on the second pole plate are in the same direction, so the second pole plate will be further pulled away from the equilibrium position, so that the distance between the pole plates changes rapidly, and the corresponding capacitance between the pole plates also changes rapidly.

因此，

所对的电压即为转折电压，当

时，有

可以得出此时的

因此有转折电压为

therefore,

The corresponding voltage is the turning voltage, when

when there is

It can be concluded that at this time

Therefore, there is a breakover voltage of

在本申请的一个实施例中，为避免第二极板在急速变化向第一极板运动的过程中，与第一极板发生撞击，从而损坏第二极板。因此，本申请实施例在MEMS加速度传感器芯片的第一极板的第一表面的边缘设置了第一限位凸点，以及在第三极板的第一表面的边缘设置了第二限位凸点。在第二极板运动碰到限位凸点的情况下，由于限位凸点的限制，第二极板将无法继续向第一极板的方向运动。此时，如果继续基于步进电压值调整第一极板与第二极板间的直流电压值，由于第二极板位置不变，因此，第一极板与第二极板间电容值不发生变化。此时，第一极板与第二极板之间的基础电容值与加压电容值的差值称为电容变化值。In an embodiment of the present application, in order to prevent the second pole plate from colliding with the first pole plate in the process of rapidly changing and moving toward the first pole plate, thereby damaging the second pole plate. Therefore, in the embodiment of the present application, the first limiting bumps are arranged on the edge of the first surface of the first plate of the MEMS acceleration sensor chip, and the second limiting bumps are arranged on the edge of the first surface of the third plate. point. When the movement of the second pole plate encounters the limiting bump, the second pole plate cannot continue to move in the direction of the first pole plate due to the restriction of the limiting bump. At this time, if you continue to adjust the DC voltage value between the first pole plate and the second pole plate based on the step voltage value, since the position of the second pole plate does not change, the capacitance value between the first pole plate and the second pole plate will not change. change. At this time, the difference between the base capacitance value and the pressure capacitance value between the first electrode plate and the second electrode plate is called a capacitance change value.

图6为本申请实施例提供的一种MEMS加速度传感器芯片的限位凸点位置结构示意图。FIG. 6 is a schematic structural diagram of a position limiting bump of a MEMS acceleration sensor chip according to an embodiment of the present application.

如图6所示，限位凸点501设置于第一极板的第一表面以及第三极板第一表面，限位凸点的大小及形状可根据实际检测需求进行调整，本申请在此不做限定。As shown in FIG. 6 , the limiting bumps 501 are disposed on the first surface of the first electrode plate and the first surface of the third electrode plate. The size and shape of the limiting bumps can be adjusted according to the actual detection requirements. Not limited.

在本申请的一个实施例中，还可以通过上述步骤103提供的方法基于获得的第二极板与第三极板之间的基础电容值和加压电容值，确定MEMS加速度传感器芯片第二极板与第三极板之间的转折电压及与电容变化值。方法与确定MEMS加速度传感器芯片第一极板与第二极板之间的转折电压及电容变化值相同，在此不再赘述。In an embodiment of the present application, the second electrode of the MEMS acceleration sensor chip can also be determined based on the obtained basic capacitance value and the pressure capacitance value between the second electrode plate and the third electrode plate by the method provided in the above step 103 The transition voltage between the plate and the third plate and the change in capacitance. The method is the same as determining the turning voltage and the capacitance change value between the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, and details are not repeated here.

步骤104、根据第一极板与第二极板的基础电容值、转折电压以及电容变化值，判断MEMS加速度传感器芯片是否正常。Step 104: Determine whether the MEMS acceleration sensor chip is normal according to the basic capacitance value, the turning voltage and the capacitance change value of the first electrode plate and the second electrode plate.

在根据MEMS加速度传感器芯片的C-V特性曲线，得到MEMS加速度传感器芯片的转折电压和电容变化值之后，判断当前MEMS加速度传感器芯片的基础电容值、转折电压、电容变化值以及C-V特性曲线，与对应的对应的基础电容值、转折电压、电容变化值以及C-V特性曲线的理论设计值的差值是否大于预设阈值。After obtaining the inflection voltage and capacitance change value of the MEMS acceleration sensor chip according to the C-V characteristic curve of the MEMS acceleration sensor chip, determine the basic capacitance value, inflection voltage, capacitance change value and C-V characteristic curve of the current MEMS acceleration sensor chip, and the corresponding Whether the difference between the corresponding basic capacitance value, corner voltage, capacitance change value and the theoretical design value of the C-V characteristic curve is greater than a preset threshold.

在当前基础电容值与对应的基础电容值的理论设计值之间的差值大于预设阈值的情况下，确定在加工当前MEMS加速度传感器芯片的过程中存在问题，从而导致MEMS加速度传感器芯片的结构参数与理论设计值存在差别。In the case that the difference between the current basic capacitance value and the theoretical design value of the corresponding basic capacitance value is greater than the preset threshold, it is determined that there is a problem in the process of processing the current MEMS acceleration sensor chip, thereby causing the structure of the MEMS acceleration sensor chip. The parameters differ from the theoretical design values.

在当前转折电压与对应的转折电压的理论设计值之间的差值大于预设阈值的情况下，同样确定在加工当前MEMS加速度传感器芯片的过程中存在问题，从而导致了MEMS加速度传感器芯片的结构参数与理论设计值存在差别。In the case where the difference between the current turning voltage and the theoretical design value of the corresponding turning voltage is greater than the preset threshold, it is also determined that there is a problem in the process of processing the current MEMS acceleration sensor chip, resulting in the structure of the MEMS acceleration sensor chip. The parameters differ from the theoretical design values.

在当前电容变化值与对应的电容变化值的理论设计值之间的差值大于预设阈值的情况下，确定当前MEMS加速度传感器芯片的第二极板不能正常的按照不同的电压值移动到相应的位置；此种情况下，说明弹性梁的加工过程可能存在问题，使第二极板无法正常运动。In the case where the difference between the current capacitance change value and the theoretical design value of the corresponding capacitance change value is greater than the preset threshold, it is determined that the second plate of the current MEMS acceleration sensor chip cannot normally move to the corresponding voltage value according to different voltage values. position; in this case, it means that there may be problems in the processing of the elastic beam, so that the second plate cannot move normally.

在当前C-V特性曲线各直流电压值对应的加压电容值与对应的C-V特性曲线的理论设计值中各直流电压值对应的加压电容值之间的差值大于预设阈值的情况下，以及在当前C-V特性曲线的整体形状与对应的C-V特性曲线的理论设计值的整体形状之间存在超出合理范围的误差的情况下，确定在加工当前MEMS加速度传感器芯片的过程中存在问题。In the case where the difference between the pressure capacitor value corresponding to each DC voltage value of the current C-V characteristic curve and the pressure capacitor value corresponding to each DC voltage value in the theoretical design value of the corresponding C-V characteristic curve is greater than a preset threshold, and When there is an error beyond a reasonable range between the overall shape of the current C-V characteristic curve and the overall shape of the corresponding theoretical design value of the C-V characteristic curve, it is determined that there is a problem in the process of machining the current MEMS acceleration sensor chip.

在本申请的一个实施例中，还可以通过上述步骤104提供的方法根据第二极板与第三极板的基础电容值、转折电压以及电容变化值，判断MEMS加速度传感器芯片是否正常。具体方法与通过第一极板与第二极板的基础电容值、转折电压、电容变化值方法相同，在此不再赘述。In an embodiment of the present application, it is also possible to judge whether the MEMS acceleration sensor chip is normal according to the basic capacitance value, the turning voltage and the capacitance change value of the second electrode plate and the third electrode plate by the method provided in the above step 104 . The specific method is the same as the method of passing the basic capacitance value, turning voltage, and capacitance change value of the first electrode plate and the second electrode plate, and will not be repeated here.

需要说明的是，只有第一极板与第二极板之间的基础电容值、转折电压、电容变化值以及C-V特性曲线和第二极板与第三极板之间的基础电容值、转折电压、电容变化值以及C-V特性曲线与对应的理论设计值误差均在合理范围内时，才可以判定MEMS加速度传感器芯片正常。It should be noted that there are only the basic capacitance value between the first pole plate and the second pole plate, the turning voltage, the capacitance change value and the C-V characteristic curve and the basic capacitance value, turning point between the second pole plate and the third pole plate. The MEMS acceleration sensor chip can be judged to be normal only when the voltage, capacitance change value, and C-V characteristic curve and the corresponding theoretical design value errors are all within a reasonable range.

还需要说明的是，本申请提供的一种MEMS加速度传感器芯片的检测方法，可以对封装前的MEMS加速度传感器芯片进行检测，也可以对封装后的MEMS加速度传感器芯片进行检测。为避免对不能正常工作的MEMS加速度传感器芯片进行封装使成本提升，建议在MEMS加速度传感器芯片封装前对其进行检测。It should also be noted that the method for detecting a MEMS acceleration sensor chip provided by the present application can detect the MEMS acceleration sensor chip before packaging, and can also detect the MEMS acceleration sensor chip after packaging. In order to avoid the cost increase due to the packaging of the MEMS acceleration sensor chip that cannot work normally, it is recommended to test the MEMS acceleration sensor chip before it is packaged.

通过本申请实施例提供的一种MEMS加速度传感器芯片的检测方法，解决了由于MEMS加速度传感器芯片可批量化生产，MEMS加速度传感器芯片封装成本又往往占整个MEMS加速度传感器芯片生产的70～80％，因此对不能正常工作的MEMS加速度传感器芯片进行封装使成本提升的问题。本申请实施例提供的一种MEMS加速度传感器芯片的检测方法，实现了在封装前对MEMS加速度传感器芯片性能的初步测试，能够排除不能正常工作的芯片，筛选出性能良好的MEMS加速度传感器芯片进行封装，极大的节约了成本。The method for detecting a MEMS acceleration sensor chip provided by the embodiment of the present application solves the problem that since the MEMS acceleration sensor chip can be mass-produced, the packaging cost of the MEMS acceleration sensor chip often accounts for 70-80% of the production of the entire MEMS acceleration sensor chip. Therefore, packaging the MEMS acceleration sensor chip that cannot work normally increases the cost. A method for detecting a MEMS acceleration sensor chip provided by an embodiment of the present application realizes a preliminary test of the performance of a MEMS acceleration sensor chip before packaging, can exclude chips that cannot work normally, and select a MEMS acceleration sensor chip with good performance for packaging. , which greatly saves costs.

基于同样的发明构思，本申请实施例还提供了一种MEMS加速度传感器芯片的检测装置，其结构示意图如图7所示。Based on the same inventive concept, an embodiment of the present application also provides a detection device for a MEMS acceleration sensor chip, the schematic diagram of which is shown in FIG. 7 .

图7为本申请实施例提供的一种MEMS加速度传感器芯片的检测装置结构示意图。如图7所示，本申请实施例提供的一种MEMS加速度传感器芯片的检测装置700包括：电压输出模块701、确定模块702、判断模块703。FIG. 7 is a schematic structural diagram of a detection device for a MEMS acceleration sensor chip according to an embodiment of the present application. As shown in FIG. 7 , a detection device 700 for a MEMS acceleration sensor chip provided by an embodiment of the present application includes: a voltage output module 701 , a determination module 702 , and a determination module 703 .

本领域技术人员可以理解，图7显示出的MEMS加速度传感器芯片的检测装置结构并不构成对MEMS加速度传感器芯片的检测装置的限定，实际上，MEMS加速度传感器芯片的检测装置可以包括比图7所示更多或更少的部件，或者组合某些部件，或者不同部件的布置。Those skilled in the art can understand that the structure of the detection device of the MEMS acceleration sensor chip shown in FIG. 7 does not constitute a limitation on the detection device of the MEMS acceleration sensor chip. show more or fewer components, or combinations of certain components, or arrangements of different components.

在本申请的一个实施例中，电压输出模块701，用于将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使第二极板朝着第一极板的方向移动；其中，MEMS加速度传感器芯片是封装前的芯片，第一极板是固定极板，第二极板是移动极板；电压输出模块701，还用于将预设频率的交流电压加在第一极板与第二极板，以获得第一极板与第二极板之间的基础电容值和加压电容值；其中，基础电容值为直流电压的电压值为零时，第一极板与第二极板之间的电容值，加压电容值为直流电压的电压值不为零时，第一极板与第二极板之间的电容值；确定模块702，用于基于获得的第一极板与第二极板之间的基础电容值和加压电容值，确定MEMS加速度传感器芯片第一极板与第二极板之间的转折电压及与电容变化值；判断模块703，用于根据第一极板与第二极板的基础电容值、转折电压以及电容变化值，判断MEMS加速度传感器芯片是否正常。In an embodiment of the present application, the voltage output module 701 is used to apply a variable DC voltage to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, so that the second electrode plate faces the first electrode plate The MEMS acceleration sensor chip is the chip before packaging, the first electrode plate is a fixed electrode plate, and the second electrode plate is a moving electrode plate; the voltage output module 701 is also used to add the AC voltage of the preset frequency to the In the first pole plate and the second pole plate, to obtain the basic capacitance value and the pressurized capacitance value between the first pole plate and the second pole plate; wherein, when the basic capacitance value is zero when the voltage value of the DC voltage is zero, the first When the capacitance value between the first electrode plate and the second electrode plate, the pressurized capacitance value is not zero and the voltage value of the DC voltage is not zero, the capacitance value between the first electrode plate and the second electrode plate; the determining module 702 is used for Based on the obtained basic capacitance value and pressurized capacitance value between the first electrode plate and the second electrode plate, determine the turning voltage and the capacitance change value between the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip; determine The module 703 is used for judging whether the MEMS acceleration sensor chip is normal according to the basic capacitance value, the turning voltage and the capacitance change value of the first electrode plate and the second electrode plate.

本申请中的各个实施例均采用递进的方式描述，各个实施例之间相同相似的部分互相参见即可，每个实施例重点说明的都是与其他实施例的不同之处。尤其，对于装置实施例而言，由于其基本相似于方法实施例，所以描述的比较简单，相关之处参见方法实施例的部分说明即可。Each embodiment in this application is described in a progressive manner, and the same and similar parts between the various embodiments may be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the apparatus embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and reference may be made to some descriptions of the method embodiments for related parts.

还需要说明的是，术语“包括”、“包含”或者其任何其他变体意在涵盖非排他性的包含，从而使得包括一系列要素的过程、方法、商品或者设备不仅包括那些要素，而且还包括没有明确列出的其他要素，或者是还包括为这种过程、方法、商品或者设备所固有的要素。在没有更多限制的情况下，由语句“包括一个……”限定的要素，并不排除在包括所述要素的过程、方法、商品或者设备中还存在另外的相同要素。It should also be noted that the terms "comprising", "comprising" or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device comprising a series of elements includes not only those elements, but also Other elements not expressly listed, or which are inherent to such a process, method, article of manufacture, or apparatus are also included. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in the process, method, article of manufacture, or device that includes the element.

以上所述仅为本申请的实施例而已，并不用于限制本申请。对于本领域技术人员来说，本申请可以有各种更改和变化。凡在本申请的精神和原理之内所作的任何修改、等同替换、改进等，均应包含在本申请的权利要求范围之内。The above descriptions are merely examples of the present application, and are not intended to limit the present application. Various modifications and variations of this application are possible for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the scope of the claims of this application.

Claims

一种MEMS加速度传感器芯片的检测方法，其特征在于，所述方法包括:将可变直流电压加在MEMS加速度传感器芯片的第一极板与第极板，以使所述第二极板朝着所述第一极板的方向移动；其中，所述第一极板是固定极板，所述第二极板是可动极板;将预设频率的交流电压加在所述第一极板与所述第二极板，以获得所述第一极板与所述第二极板之间的基础电容值和加压电容值；其中，所述基础电容值为所述直流电压的电压值为零时，所述第一极板与所述第二极板之间的电容值，所述加压电容值为所述直流电压的电压值不为零时，所述第一极板与所述第二极板之间的电容值;基于获得的所述第一极板与所述第二极板之间的基础电容值和加压电容值，确定所述MEMS加速度传感器芯片第一极板与第二极板之间的电压-电容特性曲线、转折电压以及电容变化值;根据所述第一极板与所述第二极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线，判断所述MEMS加速度传感器芯片是否正常。A detection method for a MEMS acceleration sensor chip, wherein the method comprises: adding a variable DC voltage to the first polar plate and the first polar plate of the MEMS acceleration sensor chip, so that the second polar plate is directed toward the The direction of the first pole plate moves; wherein, the first pole plate is a fixed pole plate, and the second pole plate is a movable pole plate; the AC voltage of the preset frequency is added to the first pole plate and the second pole plate to obtain the basic capacitance value and the pressure capacitance value between the first pole plate and the second pole plate; wherein, the basic capacitance value is the voltage value of the DC voltage When it is zero, the capacitance value between the first pole plate and the second pole plate, and the voltage value of the pressurized capacitance value are not zero when the voltage value of the DC voltage is not zero, the first pole plate and all The capacitance value between the second pole plates; based on the obtained basic capacitance value and the pressure capacitance value between the first pole plate and the second pole plate, determine the first pole plate of the MEMS acceleration sensor chip Voltage-capacitance characteristic curve, inflection voltage and capacitance change value between the second pole plate; according to the basic capacitance value, inflection voltage, capacitance change value and voltage between the first pole plate and the second pole plate -Capacitance characteristic curve to judge whether the MEMS acceleration sensor chip is normal.
根据权利要求1所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，所述方法还包括:确定MEMS加速度传感器芯片第二极板与第三极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线;将所述MEMS加速度传感器芯片第二极板与第三极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线与MEMS加速度传感器芯片第二极板与第三极板之间对应的基础电容值、转折电压、电容变化值以及电压-电容特性曲线的理论设计值进行对比，判断所述MEMS加速度传感器芯片是否正常。The detection method of a kind of MEMS acceleration sensor chip according to claim 1, is characterized in that, described method also comprises: determine the basic capacitance value between the second polar plate and the third polar plate of MEMS acceleration sensor chip, inflection voltage , capacitance change value and voltage-capacitance characteristic curve; the basic capacitance value, turning voltage, capacitance change value and voltage-capacitance characteristic curve between the second plate and the third plate of the MEMS acceleration sensor chip and the MEMS acceleration sensor The basic capacitance value, the turning voltage, the capacitance change value and the theoretical design value of the voltage-capacitance characteristic curve corresponding to the second electrode plate and the third electrode plate of the chip are compared to determine whether the MEMS acceleration sensor chip is normal.
根据权利要求1所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，所述将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使所述第二极板朝着所述第一极板的方向移动，具体包括：The detection method of a MEMS acceleration sensor chip according to claim 1, wherein the variable DC voltage is applied to the first plate and the second plate of the MEMS acceleration sensor chip, so that the first plate and the second plate of the MEMS acceleration sensor chip are applied. The movement of the diode plate towards the direction of the first plate specifically includes:

将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板；The variable DC voltage is applied to the first plate and the second plate of the MEMS acceleration sensor chip;

基于预设的步进电压值，调整所述直流电压值，以使所述第二极板朝着所述第一极板的方向移动；Based on a preset step voltage value, adjusting the DC voltage value so that the second pole plate moves in the direction of the first pole plate;

其中，所述第二极板的移动距离由当前直流电压值决定。Wherein, the moving distance of the second pole plate is determined by the current DC voltage value.
根据权利要求3所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，所述基于预设的步进电压值，调整所述直流电压的输出电压值，以使所述第二极板朝着所述第一极板的方向移动，具体包括：The detection method of a MEMS acceleration sensor chip according to claim 3, wherein the output voltage value of the DC voltage is adjusted based on a preset step voltage value, so that the second electrode plate Moving towards the direction of the first polar plate, specifically including:

基于预设的步进电压值调整直流电压值，以使所述第一极板与所述第二极板之间获得不同的直流电压值，以基于所述不同的直流电压值在所述第一极板与所述第二极板之间产生不同大小的静电力，用以克服基于第二极板移动引起弹性梁形变，所产生的弹性力；其中，所述弹性梁为连接在MEMS加速度传感器芯片第二极板上的组件。The DC voltage value is adjusted based on the preset step voltage value, so that different DC voltage values are obtained between the first electrode plate and the second electrode plate, so that the first electrode plate and the second electrode plate can obtain different DC voltage values based on the different DC voltage values. Electrostatic forces of different magnitudes are generated between a pole plate and the second pole plate to overcome the elastic force generated by the deformation of the elastic beam caused by the movement of the second pole plate; wherein, the elastic beam is connected to the MEMS acceleration Components on the second plate of the sensor chip.
根据权利要求1所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，所述将预设频率的交流电压加在所述第一极板与所述第二极板，以获得所述第一极板与所述的第二极板之间的基础电容值和加压电容值，具体包括：The detection method of a MEMS acceleration sensor chip according to claim 1, wherein the AC voltage of a preset frequency is applied to the first electrode plate and the second electrode plate to obtain the The basic capacitance value and the pressure capacitance value between the first electrode plate and the second electrode plate specifically include:

将预设频率的交流电压加在所述MEMS加速度传感器芯片的第一极板与第二极板，以使所述第一极板与所述第二极板之间产生电流；adding an alternating voltage of a preset frequency to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, so that a current is generated between the first electrode plate and the second electrode plate;

基于所产生的电流信息，计算所述第一极板与所述第二极板之间的基础电容值和加压电容值；其中，所述电流信息包括电流的幅值及相位。Based on the generated current information, a basic capacitance value and a pressurized capacitance value between the first electrode plate and the second electrode plate are calculated; wherein the current information includes the amplitude and phase of the current.
根据权利要求1所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，所述转折电压为公式
结果等于零的情况，V所对应的电压值； The detection method of a MEMS acceleration sensor chip according to claim 1, wherein the turning voltage is a formula
When the result is equal to zero, the voltage value corresponding to V;

其中，ε为所述第一极板与所述第二极板间介质的介电常数，A为所述第一极板与所述第二极板的极板面积，V为加在所述第一极板与所述第二极板之间的直流电压值，d为所述第一极板与所述第二极板的极板间距，k为所述弹性梁的弹性系数。Wherein, ε is the dielectric constant of the medium between the first electrode plate and the second electrode plate, A is the electrode plate area of the first electrode plate and the second electrode plate, and V is the value added to the The DC voltage value between the first pole plate and the second pole plate, d is the pole plate distance between the first pole plate and the second pole plate, and k is the elastic coefficient of the elastic beam.
根据权利要求1所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，所述根据所述第一极板与所述第二极板的基础电容值、转折电压以及电容变化值，判断所述MEMS加速度传感器芯片是否正常，具体包括：The detection method of a MEMS acceleration sensor chip according to claim 1, wherein the judgment is based on the basic capacitance value, the turning voltage and the capacitance change value of the first electrode plate and the second electrode plate. Whether the MEMS acceleration sensor chip is normal, specifically including:

将当前所述MEMS加速度传感器芯片第一极板与第二极板之间的基础电容值、转折电压、电容变化值以及电压-电容特性曲线，与MEMS加速度传感器芯片第一极板与第二极板之间对应的基础电容值、转折电压、电容变化值以及电压-电容特性曲线的理论设计值，进行对比；Compare the basic capacitance value, turning voltage, capacitance change value, and voltage-capacitance characteristic curve between the first plate and the second plate of the MEMS acceleration sensor chip with the first plate and the second plate of the MEMS acceleration sensor chip. The corresponding basic capacitance value, turning voltage, capacitance change value and theoretical design value of the voltage-capacitance characteristic curve between the plates are compared;

在当前所述基础电容值、转折电压、电容变化值以及电压-电容特性曲线中的任意一项或多项，与对应的基础电容值、转折电压、电容变化值以及电压-电容特性曲线的理论设计值的差值大于预设阈值的情况下，确定所述MEMS加速度传感器芯片不正常。Any one or more of the current basic capacitance value, corner voltage, capacitance change value and voltage-capacitance characteristic curve, and the corresponding basic capacitance value, corner voltage, capacitance change value and the theoretical value of the voltage-capacitance characteristic curve When the difference between the design values is greater than the preset threshold, it is determined that the MEMS acceleration sensor chip is abnormal.
根据权利要求1所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，在直流电压值不为零时，所述交流电压峰值绝对值的预设倍数小于所述直流电压值的绝对值。The method for detecting a MEMS acceleration sensor chip according to claim 1, wherein when the DC voltage value is not zero, the preset multiple of the absolute value of the peak value of the AC voltage is smaller than the absolute value of the DC voltage value .
根据权利要求1所述的一种MEMS加速度传感器芯片的检测方法，其特征在于，在将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使所述第二极板朝着所述第一极板的方向移动之前，所述方法还包括：A method for detecting a MEMS acceleration sensor chip according to claim 1, wherein a variable DC voltage is applied to the first plate and the second plate of the MEMS acceleration sensor chip, so that the second plate Before the pole plate moves in the direction of the first pole plate, the method further includes:

在所述MEMS加速度传感器芯片的第一极板的第一表面的边缘设置第一限位凸点，以及在第三极板的第一表面的边缘设置第二限位凸点，用以避免在所述直流电压提供的电压值下使得所述第二极板移动过程中与所述第一极板或者所述第三极板接触。A first limiting bump is arranged on the edge of the first surface of the first plate of the MEMS acceleration sensor chip, and a second limiting bump is arranged on the edge of the first surface of the third plate to avoid the Under the voltage value provided by the DC voltage, the second electrode plate is in contact with the first electrode plate or the third electrode plate during the movement process.
一种MEMS加速度传感器芯片的检测装置，其特征在于，所述装置包括：A detection device for a MEMS acceleration sensor chip, characterized in that the device comprises:

电压输出模块，用于将可变直流电压加在MEMS加速度传感器芯片的第一极板与第二极板，以使所述第二极板朝着所述第一极板的方向移动；其中，所述第一极板是固定极板，所述第二极板是可动极板；The voltage output module is used to apply a variable DC voltage to the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip, so that the second electrode plate moves in the direction of the first electrode plate; wherein, The first pole plate is a fixed pole plate, and the second pole plate is a movable pole plate;

所述电压输出模块，还用于将预设频率的交流电压加在所述第一极板与所述第二极板，以获得所述第一极板与所述第二极板之间的基础电容值和加压电容值；其中，所述基础电容值为所述直流电压的电压值为零时，所述第一极板与所述第二极板之间的电容值，所述加压电容值为所述直流电压的电压值不为零时，所述第一极板与所述第二极板之间的电容值；The voltage output module is also used to apply the AC voltage of the preset frequency to the first pole plate and the second pole plate to obtain the voltage between the first pole plate and the second pole plate. The basic capacitance value and the pressing capacitance value; wherein, the basic capacitance value is the capacitance value between the first electrode plate and the second electrode plate when the voltage value of the DC voltage is zero, and the adding The piezoelectric capacitance value is the capacitance value between the first electrode plate and the second electrode plate when the voltage value of the DC voltage is not zero;

确定模块，用于基于获得的所述第一极板与所述第二极板之间的基础电容值和加压电容值，确定所述MEMS加速度传感器芯片第一极板与第二极板之间的电压-电容特性曲线、转折电压以及电容变化值；A determination module is used to determine the difference between the first electrode plate and the second electrode plate of the MEMS acceleration sensor chip based on the obtained basic capacitance value and the pressure capacitance value between the first electrode plate and the second electrode plate Voltage-capacitance characteristic curve, corner voltage and capacitance change value between

判断模块用于，根据所述第一极板与所述第二极板的基础电容值、转折电压、电容变化值以及电压-电容特性曲线，判断所述MEMS加速度传感器芯片是否正常。The judging module is used for judging whether the MEMS acceleration sensor chip is normal according to the basic capacitance value, turning voltage, capacitance change value and voltage-capacitance characteristic curve of the first electrode plate and the second electrode plate.