CN107960008B

CN107960008B - Integrated circuit board

Info

Publication number: CN107960008B
Application number: CN201711424428.9A
Authority: CN
Inventors: 胡静
Original assignee: Zhejiang Changshan Juhua Electronic Co Ltd
Current assignee: Zhejiang Changshan Juhua Electronic Co., Ltd
Priority date: 2017-12-25
Filing date: 2017-12-25
Publication date: 2020-06-12
Anticipated expiration: 2037-12-25
Also published as: CN107960008A

Abstract

The present invention provides an integrated circuit board, comprising: the PCB board is provided with a groove body; a metal layer formed on a bottom surface of the tank body; an insulating layer formed on an upper surface of the metal layer; an array gas sensor formed on an upper surface of the insulating layer and arranged at the upper surface of the insulating layer in an array; conductive contacts disposed on the metal layer and extending to an upper surface of the insulating layer to connect the array gas sensor with an external circuit; an air gap formed on the upper portion of the array gas sensor after the sacrificial layer on the upper portion of the array gas sensor is removed; a support pillar formed in the air gap; and a metal cover layer formed on the upper part of the support column and having at least one vent hole at the cover layer for introducing gas into the air gap to contact the array gas sensor. The integrated circuit board integrates the gas sensor and the capacitor on the PCB of the integrated circuit board, so that raw materials are saved, and the PCB is utilized to the maximum extent.

Description

Integrated circuit board

Technical Field

The present invention relates to the field of integrated circuit technology, and more particularly, to an integrated circuit board.

Background

The integrated circuit boards can be classified into analog integrated circuit boards and digital integrated circuit boards according to their functions and structures. Analog is used to generate, amplify and process various analog signals (i.e., signals whose amplitude varies with time, such as audio signals for semiconductor radios, tape signals for recorders, etc.), while digital is used to generate, amplify and process various digital signals (i.e., signals whose values are discrete in time and amplitude, such as audio and video signals for VCD, DVD playback).

The gas sensor can form independent classification standards from the working principle, characteristic analysis to the measurement technology, the used materials to the manufacturing process, and the detection object to the application field, and a complicated and complicated classification system is derived. The gas sensor mainly has the following characteristics: stability, sensitivity, selectivity and corrosion resistance.

Stability refers to the stability of the sensor response over substantially the entire operating time, depending on zero drift and interval drift. Zero drift refers to the change in sensor output response over the entire operating time in the absence of the target gas. Interval drift is the change in output response of a sensor continuously placed in a target gas, manifested as a decrease in the sensor output signal over operating time. Ideally, one sensor has a zero drift of less than 10% per year under continuous operating conditions.

Sensitivity is the ratio of the amount of change in sensor output to the amount of change in measured input, and is primarily dependent on the technology used in the sensor structure. Most gas sensors are designed on the principles of biochemistry, electrochemistry, physics, and optics. The first consideration is to choose a sensitive technique that is sufficiently sensitive to detect the percentage of the valve limit (TLV-thresh-oldlimitvalue) or the lowest explosion limit (LEL-lowerexplosivelimit) of the target gas.

Selectivity is also referred to as cross-sensitivity. Can be determined by measuring the sensor response produced by a concentration of interfering gas. This response is equivalent to the sensor response generated by a concentration of the target gas. This characteristic is very important in applications tracking multiple gases, because cross-sensitivity reduces measurement repeatability and reliability, and an ideal sensor should have high sensitivity and high selectivity.

Corrosion resistance refers to the ability of the sensor to be exposed to a high volume fraction of the target gas. When a large amount of gas leaks, the probe can bear 10-20 times of the expected volume fraction of the gas. The sensor drift and zero correction values should be as small as possible upon return to normal operating conditions.

The basic characteristics of a gas sensor, i.e., sensitivity, selectivity, stability, etc., are determined primarily by the choice of materials. The method selects proper materials and develops new materials to optimize the sensitivity of the gas sensor.

At present, the substrate of the integrated circuit board is usually a PCB board, and when the gas sensor and the capacitor are integrated together and connected with the integrated circuit board, the separate gas sensor and the separate capacitor are respectively connected with the integrated circuit board. With such a configuration, the device is larger in volume and heavier in weight due to the fact that three separate devices are arranged together, and the current trend of miniaturization is not satisfied.

Disclosure of Invention

In order to solve the above technical problem, the present invention provides an integrated circuit board, including:

the PCB board is provided with a groove body;

a metal layer formed on a bottom surface of the tank body;

an insulating layer formed on an upper surface of the metal layer;

an array gas sensor formed on an upper surface of the insulating layer and arranged at the upper surface of the insulating layer in an array;

conductive contacts disposed on the metal layer and extending to an upper surface of the insulating layer to connect the array gas sensor with an external circuit;

a gas gap formed at an upper portion of the array gas sensor after removal of a sacrificial layer at the upper portion of the array gas sensor;

a support post formed in the air gap; and

a metal cap layer formed on the upper portion of the support posts and having at least one vent hole at the cap layer for introducing gas into the air gap to make contact with the array gas sensor.

The insulating layer is in a concave shape and comprises a bottom wall and a side wall, and the thickness of the bottom wall of the insulating layer is smaller than that of any side wall of two side surfaces of the insulating layer.

Further, the metal layer and the metal cap layer serve as two electrodes of a capacitor.

Further, the integrated circuit board further includes:

one end of the first conducting wire is contacted with the conductive contact, and the other end of the first conducting wire is connected with the external circuit;

the first lead is buried in a side wall of the insulating layer.

Further, the integrated circuit board further includes:

one end of the second lead is contacted with the metal cover layer, and the other end of the second lead is connected with the external circuit;

wherein the second wire is buried in the sidewall of the insulating layer.

Furthermore, the metal layer is a metal film, and the thickness of the metal film is 100-1000 nm.

Further, the supporting column is an insulator.

Further, the metal cover layer is arranged to be just flush with the plane of the opening of the groove body.

Furthermore, the insulating layer is made of a flexible polymer material.

Further, the thickness of the air gap is more than 2 times of the sum of the thicknesses of the insulating layer and the metal cover layer.

Further, the array gas sensor is a circular array or a square array.

According to the scheme of the invention, the integrated circuit board integrates the gas sensor and the capacitor on the PCB of the integrated circuit board, thereby not only saving raw materials and utilizing the PCB to the maximum extent, but also greatly reducing the volume and the quality by integrating three devices into one device. In addition, lead the first wire from the diapire of insulating layer to on the lateral wall to bury and cover in the insulating layer, on the one hand, have very strong guard action to first wire, be unlikely to expose the electrically conductive away, increase the reliability, on the other hand, lead out first wire to the lateral wall from the diapire, greatly made things convenient for the setting of outer circuit, and pleasing to the eye outward appearance, be unlikely to that the wiring is in disorder. The second conductive line is also embedded in the insulating layer, and has the same effect as the first conductive line. In addition, due to the formation of the air gap, external air can be fully contacted with the sensing sites of the array gas sensor, and the sensitivity of the array gas sensor is greatly improved.

The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.

Drawings

Some specific embodiments of the invention will be described in detail hereinafter, by way of illustration and not limitation, with reference to the accompanying drawings.

The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

fig. 1 is a schematic block diagram of an integrated circuit board according to an embodiment of the present invention.

Reference numerals:

10-a PCB board, wherein the PCB board is provided with a plurality of PCB grooves,

101-a tank body, wherein the tank body,

20-a layer of a metal,

30-an insulating layer, the insulating layer,

40-an array of gas sensors, the array comprising a plurality of gas sensors,

50-the electrically conductive contact(s) are,

60-an air gap is formed between the upper part and the lower part,

70-a support column, wherein the support column,

80-a metal cover layer, wherein the metal cover layer,

801-a vent hole, wherein the vent hole is provided with a vent hole,

90-the first conducting wire, the second conducting wire,

100-second conductor.

Detailed Description

Fig. 1 shows a schematic block diagram of an integrated circuit board according to an embodiment of the present invention. As shown in fig. 1, the integrated circuit board includes: a PCB board 10 having a slot 101; a metal layer 20 formed on the bottom surface of the tank body 101; an insulating layer 30 formed on an upper surface of the metal layer 20; an array gas sensor 40 formed on an upper surface of the insulating layer 30 and arranged at the upper surface of the insulating layer 30 in an array; a conductive contact 50 disposed on the metal layer 20 and extending to an upper surface of the insulating layer 30 to connect the array gas sensor 40 with an external circuit; a gas gap 60 formed at an upper portion of the array gas sensor 40 after removal of a sacrificial layer at the upper portion of the array gas sensor 40; support posts 70 formed in the air gaps 60; and a metal cover layer 80 formed on the upper portion of the support pillar 70 and having at least one vent hole 801 at the cover layer for introducing gas into the air gap 60 to contact the array gas sensor 40.

In a preferred embodiment, the integrated circuit board comprises power contact pads. The set of power contact pads includes power contact pads of corresponding adjacent gas sensor chips. This means that the gas sensor chips, whose heaters are simultaneously supplied with current, are arranged next to one another on a carrier. Adjacent means that they are arranged one next to the other in any direction.

The array gas sensor 40 includes a sensing layer, which may be comprised of a material that is sensitive to one or more analytes. The sensitive layer may comprise a plurality of separate layer portions arranged adjacent to each other and spaced apart from each other to build up a sensor array comprising groups of sensor cells, wherein a sensor cell may be understood as an entity of a gas sensor that can be read individually. Preferably, in an embodiment of the sensor array, each or at least some of the layer portions are adapted to sense an analyte, in particular to sense a different analyte. Analytes may include, for example, one or more of H2O, CO2, NOX, ethanol, CO, ozone, ammonia, formaldehyde, or xylene, but are not limited thereto. In particular, the sensitive layer may contain a metal oxide material, in particular a semiconductive metal oxide material, in particular a metal oxide material having a different composition in each layer portion. The metal oxide material may generally include one or more of tin oxide, zinc oxide, titanium oxide, tungsten oxide, indium oxide, and gallium oxide. Such metal oxides can be used to detect analytes such as VOCs, carbon monoxide, nitrogen dioxide, methane, ammonia, or hydrogen sulfide. The metal oxide sensor is based on the principle that gaseous analytes interact with the metal oxide layer at elevated temperatures of the sensitive layer, which are in the range above 100 ℃, in particular between 250 ℃ and 350 ℃. The conductivity of the sensitive layer may change due to the catalytic reaction, which can be measured. Such a chemical sensor is therefore also referred to as a high temperature chemiresistor, for the reason of converting the chemical nature of the analyte into a resistance at the high temperature of the sensitive layer. Preferably, with such a gas sensor, a gas can be investigated at least with regard to the presence or absence of a subject analyte to which the gas sensor is sensitive. Thus, the gas provided to the gas sensor can be analyzed by the sensing layer to determine whether and which sensitive chemicals or mixtures the sensing layer is sensitive to are present in the provided gas. The combination of analytes detected in the provided gas may exhibit a certain odor. The subject of the design of gas sensors is always how many different analytes the gas sensor is sensitive to and/or how many different properties of the analytes the gas sensor is sensitive to.

In one embodiment, the insulating layer 30 is configured in a "concave" shape, and includes a bottom wall and a side wall, and the bottom wall of the insulating layer 30 has a thickness smaller than that of any one of the two side surfaces of the insulating layer 30.

In a preferred embodiment, the metal layer 20 and the metal cap layer 80 serve as two electrodes of a capacitor.

Wherein, integrated circuit board still includes: a first wire 90 having one end contacting the conductive contact 50 and the other end connected to the external circuit; wherein the first conductive line 90 is buried in a sidewall of the insulating layer 30. The integrated circuit board further includes: a second conductive line 100 having one end contacting the metal cap layer 80 and the other end connected to the external circuit; wherein the second conductive line 100 is buried in a sidewall of the insulating layer 30.

In one embodiment, the metal layer 20 is a metal thin film, and the thickness of the metal thin film is 100 nm, 300nm, 600nm or 1000nm, or any value of 100 nm and 1000 nm.

The support posts 70 are insulators. The metal cover layer 80 is arranged to be just flush with the plane of the opening of the groove body 101. The insulating layer 30 is made of a flexible polymer material. The thickness of the air gap 60 is greater than 2 times the sum of the thicknesses of the insulating layer 30 and the metal cap layer 80. The array gas sensor 40 is a circular array or a square array.

According to the scheme of the invention, the integrated circuit board integrates the gas sensor and the capacitor on the PCB board 10 of the integrated circuit board, thereby not only saving raw materials and utilizing the PCB board 10 to the maximum extent, but also integrating three devices into one device and greatly reducing the volume and the quality. In addition, the first lead 90 is led to the side wall from the bottom wall of the insulating layer 30 and is buried in the insulating layer 30, on one hand, the first lead 90 is protected strongly, the electric conduction is not exposed, and the reliability is increased, on the other hand, the first lead 90 is led out from the bottom wall to the side wall, so that the arrangement of an external circuit is greatly facilitated, the appearance is attractive, and the wiring is not messy. The second conductive line 100 is also embedded in the insulating layer 30, and has the same effect as the first conductive line 90. In addition, due to the formation of the air gap 60, the external air can be sufficiently in contact with the sensing site of the array gas sensor 40, and the sensitivity of the array gas sensor 40 is greatly improved.

Thus, it should be appreciated by those skilled in the art that while a number of exemplary embodiments of the invention have been illustrated and described in detail herein, many other variations or modifications consistent with the principles of the invention may be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be understood and interpreted to cover all such other variations or modifications.

Claims

1. An integrated circuit board, comprising:

the PCB board is provided with a groove body;

a metal layer formed on a bottom surface of the tank body;

an insulating layer formed on an upper surface of the metal layer;

a support post formed in the air gap;

a metal cap layer formed on the upper part of the support pillar and having at least one vent hole at the metal cap layer for introducing gas into the air gap to contact the array gas sensor;

the insulating layer is in a concave shape and comprises a bottom wall and a side wall, and the thickness of the bottom wall of the insulating layer is smaller than that of any side wall of two side surfaces of the insulating layer;

the metal layer and the metal cover layer are used as two electrodes of a capacitor;

the integrated circuit board further includes: one end of the first conducting wire is contacted with the conductive contact, and the other end of the first conducting wire is connected with the external circuit; wherein the first conducting wire is buried in the side wall of the insulating layer;

the integrated circuit board further includes: one end of the second lead is contacted with the metal cover layer, and the other end of the second lead is connected with the external circuit; the second lead is buried in the side wall of the insulating layer;

the metal layer is a metal film, and the thickness of the metal film is 100-1000 nm;

the supporting column is an insulator;

the metal cover layer is arranged to be just flush with the plane of the opening of the groove body;

the insulating layer is made of a flexible high polymer material;

the thickness of the air gap is more than 2 times of the sum of the thicknesses of the insulating layer and the metal cover layer;

the array gas sensor is a circular array or a square array.