CN104677261A - Standard silicon wafer thickness measuring device - Google Patents

Abstract

The invention relates to a standard silicon wafer thickness measuring device. The standard silicon wafer thickness measuring device consists of a high-precision inductor micrometer, a granite framework structure and a liftable precious stone spherical surface worktable, wherein the granite framework structure is a double-layer worktable, an upper layer working platform is a silicon wafer carrier table for carrying a measured standard silicon wafer, a lower layer worktable is a base, the base is provided with a five adjustable supporting legs which are connected with the silicon wafer carrier table, the liftable precious stone spherical worktable and an inductor micrometer positioning framework are fixedly arranged on the base, the side surface of the inductor micrometer positioning framework is connected with the high-precision inductor micrometer by virtue of threads, the ribbed liftable precious stone spherical worktable with a ruby measuring head and the diameter of 60mm is arranged in the center of the silicon wafer carrier table below the inductor micrometer, the measuring head is right opposite to the center of the lower liftable precious stone spherical surface worktable, and when the thickness of a silicon wafer is measured, the silicon wafer is arranged between the ruby measuring head and the inductor micrometer. The device is suitable for calibration of the thickness of the standard silicon wafer with the diameter less than or equal to 305mm. The standard silicon wafer thickness measuring device has characteristics of compact structure, simplicity in operation, high accuracy and good reliability.

Description

Standard silicon chip measurer for thickness

Technical field

The present invention relates to a kind of measurement mechanism, especially standard silicon chip measurer for thickness.

Background technology

Standard silicon chip be each silicon chip and integrated circuit production firm in silicon chip production run for controlling the standard model of silicon wafer thickness.Be benchmark with standard silicon chip in production line, with the thickness of the method measurement products silicon chip compared and measured.The standard silicon chip of production firm comes into operation after being calibrated by metrological service.The parameter that standard silicon chip need measure has: thickness, flatness and integrated circuit standard figure etc.Standard silicon chip has the characteristics such as area is large, thickness is little, frangible, flatness is low, and there is no suitable instrument at present can be used for standard silicon chip thickness measure, also can supply without ready-made equipment both at home and abroad.

Summary of the invention

The technical matters that the application will solve is to overcome above-mentioned defect, provides a kind of standard silicon chip measurer for thickness.

For solving the problems of the technologies described above, the technical scheme of employing is:

Standard silicon chip measurer for thickness, by high precision inductance amesdial, grouan framed structure, liftable jewel sphere worktable forms, grouan framed structure is double layer working bench, upper strata workbench is that silicon wafer bearing table carries tested standard silicon chip, flatness is 2 μm, lower floor's worktable is base, base there are five adjustable support foots be connected with silicon wafer bearing table, fixing carrying liftable jewel sphere worktable and inductance amesdial positioning framework on base, inductance amesdial positioning framework side is spirally connected high precision inductance amesdial, high precision inductance amesdial resolution is 0.1 μm, range 1800 μm, the diameter that silicon wafer bearing table central authorities below inductance amesdial arrange band ruby gauge head is that 60mm is with muscle liftable jewel sphere worktable, its gauge head is just to the center of below liftable jewel sphere worktable, liftable jewel sphere vertical displacement of stage regulates sensitivity to be 0.1 μm, when measuring silicon wafer thickness, silicon chip is between ruby gauge head and inductance amesdial.

The invention has the beneficial effects as follows: package unit is applicable to the thickness calibration that diameter is not more than 305mm standard silicon chip, to the standard silicon chip of different diameters and thickness, uncertainty of measurement reaches 0.2 μm, there is compact conformation, easy and simple to handle, accuracy is high, the feature of good reliability, achieve the magnitude tracing of standard silicon chip thickness.

Accompanying drawing explanation

Fig. 1 is measurement mechanism schematic diagram.

Wherein, 1-high precision inductance amesdial; The tested standard silicon chip of 2-; 3-measuring table and base; 4-liftable jewel sphere worktable.

Embodiment

Standard silicon chip measurer for thickness is made up of high precision inductance amesdial, grouan framed structure and adjustable ruby sphere worktable three part.It is applicable to the thickness calibration of diameter 305mm (12inch) standard silicon chip.To the standard silicon chip of different diameters and thickness, perpendicular to surface direction, realize point-to-point measurement, the uncertainty of measurement of calibration criterion silicon wafer thickness is 0.2 μm.Grouan framed structure is double layer working bench, upper strata workbench is silicon wafer bearing table, the silicon chip that diameter is greater than 305mm (12inch) can be carried, workplace flatness is 2 μm, lower floor's worktable is base, there are five adjustable support foots to be connected with upper strata workbench, and carry adjustable ruby sphere worktable and inductance amesdial positioning framework (Fig. 1).High precision inductance amesdial resolution is 0.1 μm, range 1800 μm, and measure the relatively little degree of certainty 0.5% of indicating value, its gauge head is positioned on the adjustable support on grouan framework, with the central authorities of the ruby worktable of below to center.Adjustable ruby sphere vertical displacement of stage regulates sensitivity to be 0.1 μm.Before measurement standard silicon wafer thickness, zero setting after inductance amesdial and ruby worktable central contact.The thickness of tested silicon chip is predicted, after the basic size obtaining silicon wafer thickness, inductance amesdial is determined at the enterprising rower of horizontal metroscope that uncertainty of measurement is 0.08 μm, nonlinear compensation is realized by revising its error of indication, then, inductance amesdial is arranged on standard silicon chip measurer for thickness, the diverse location of silicon chip is measured.Seminar adopts granite surface plate horizontal setting silicon chip, large to adapt to silicon area, the characteristics such as thickness is thin, frangible.High precision inductance amesdial is adopted to measure the thickness of silicon chip, to adapt to the demand of various thickness and thickness uniformity.Inductance amesdial dynamometry is less, and when 200 μm of ranges, dynamometry is 0.85N, and when 900 μm of ranges, dynamometry is 0.96N, and this silicon chip being conducive to preventing dynamometry from causing is damaged, and reduces the measurement distortion that dynamometry causes.The experiment proved that, when dynamometry is 1N and 2N, the variation in thickness that the distortion of standard silicon chip causes is less than 0.05 μm.But inductance amesdial is amount of nonlinearity instrument, in 200 μm of ranges, deviation of reading is less than 0.1 μm; When 900 μm of ranges, deviation of reading then has 6 μm.And the dial gauge of internal inductance among a small circle at 900 μm of range places linearly.Deviation of reading after measured within the scope of 900 μm of range place ± 4 μm is less than 0.1 μm, therefore, when the thickness of measurement standard silicon chip, first through prediction, then is demarcated on high precision horizontal metroscope by inductance amesdial, to improve the accuracy of measurement.Standard silicon chip area is large, and thickness is thin, and its flatness can not be very well.During measurement, there is gap at bottom surface and the worktable center of standard silicon chip, measurement result may be caused to be greater than physical size value when dynamometry is very little.The granite surface plate central authorities of the carrying silicon chip below inductance amesdial arrange and are with the diameter of ruby gauge head to be that 60mm is with muscle surveying work platform, and this worktable can carry out lift adjustment, and ruby gauge head sphere top is higher than band muscle worktable 4 μm.When measuring silicon wafer thickness, silicon chip is between ruby gauge head and inductance amesdial; When jacking surveying work platform, can be observed inductance amesdial and follow rising, to guarantee that standard silicon chip bottom surface contacts with central ruby gauge head.Be standard silicon chip thickness with regard to the distance obtained between inductance amesdial gauge head to ruby gauge head thus.Through experimental verification, when being measured as 0.85N, the silicon chip of 200 μm of thickness is have nearly 30 μm of downward elastic displacements within the scope of 70mm at diameter.When being measured as 0.96N, the silicon chip of 900 μm of thickness has nearly 20 μm of downward elastic displacements within the scope of diameter 70mm.It can be confirmed ruby gauge head sphere top and band muscle workbench equal-height, in measuring process, silicon chip bottom surface contacts all the time with central ruby gauge head, thus gap deviation is asked in the measurement that elimination is caused by flatness, realizes the point-to-point measurement at vertical silicon chip surface.

Claims (1)

1. standard silicon chip measurer for thickness, it is characterized in that: by high precision inductance amesdial, grouan framed structure, liftable jewel sphere worktable forms, grouan framed structure is double layer working bench, upper strata workbench is that silicon wafer bearing table carries tested standard silicon chip, flatness is 2 μm, lower floor's worktable is base, base there are five adjustable support foots be connected with silicon wafer bearing table, fixing carrying liftable jewel sphere worktable and inductance amesdial positioning framework on base, inductance amesdial positioning framework side is spirally connected high precision inductance amesdial, high precision inductance amesdial resolution is 0.1 μm, range 1800 μm, the diameter that silicon wafer bearing table central authorities below inductance amesdial arrange band ruby gauge head is that 60mm is with muscle liftable jewel sphere worktable, its gauge head is just to the center of below liftable jewel sphere worktable, liftable jewel sphere vertical displacement of stage regulates sensitivity to be 0.1 μm, when measuring silicon wafer thickness, silicon chip is between ruby gauge head and inductance amesdial.