CN203083519U

CN203083519U - Non-contact silicon chip thickness and resistivity detection system

Info

Publication number: CN203083519U
Application number: CN 201320081742
Authority: CN
Inventors: 朱洪伟; 曹伟兵
Original assignee: SHANGHAI BERLING TECHNOLOGY Co Ltd
Current assignee: SHANGHAI BERLING TECHNOLOGY Co Ltd
Priority date: 2013-02-21
Filing date: 2013-02-21
Publication date: 2013-07-24
Anticipated expiration: 2023-02-21

Abstract

The utility model provides a non-contact silicon chip thickness and resistivity detection system which comprises a testing module. A signal processing module is connected with the testing module; a control module is connected with the signal processing module; the testing module comprises a base; upper and lower capacitive sensors are arranged on the base by probe fixing frames; the upper and lower capacitive sensors are connected with a first signal processing unit by an amplifying circuit; upper and lower eddy current sensors are also arranged on the base by probe fixing frames; the upper and lower eddy current sensors are connected with a second signal processing unit by an oscillating circuit; the control module comprises a microprocessor; and both an analog-digital and digital-to-analog conversion processor and an LCD (Liquid Crystal Display) touch screen are connected with the microprocessor. The system provided by the utility model can be used for carrying out non-contact testing on the thickness, the thickness deviation and the resistivity of a crystal-silicon solar silicon chip only by operation for once and has the characteristics of strong anti-interference capacity, strong adaptive capacity to environment, low fault rate, convenience for operation and low maintenance cost.

Description

A kind of non-contact type silicon wafer thickness resistivity detection system

Technical field

The utility model relates to a kind of non-contact type silicon wafer thickness resistivity detection system, belongs to silicon chip checkout equipment field.

Background technology

The crystal silicon solar batteries technology is a mainstream technology in occupation of absolute predominance in field of photovoltaic power generation, and the crystal silicon solar batteries sheet mainly is made up of the solar energy grade silicon chip.For guaranteeing that crystal silicon solar batteries sheet conversion efficiency satisfies technical indicator, in process of production, various parameters such as the thickness of silicon chip, thickness deviation, body resistivity all will be through test, to satisfy solar industry or client's technical indicator.At present, have two kind equipments can test these parameters, a class is traditional contact testing apparatus, and an other class is the non-contact type testing apparatus.

The contact method of testing needs two kinds of testing apparatuss respectively the thickness and the body resistivity of silicon chip to be tested, the general test of finishing thickness earlier with thickness measuring equipment, and then the resistivity of silicon chip is tested with the resistivity testing apparatus, silicon wafer thickness generally with the clock gauge test, generally test with four point probe by body resistivity.Can cause with several different testing equipments that the test data error is big, the test duration is long, production efficiency is low, the percentage of damage of silicon chip also can improve.

And the non-contact type testing apparatus all is to control by PC in the market, its control system generally all is based on the windows platform exploitation, the data response time is long, easily owing to the software maloperation causes equipment failure, equipment uses back control system reflection slack-off for a long time, the equipment service efficiency is low, and cost is also high, all is not enough to satisfy the needs of current increasingly competitive photovoltaic industry.

The utility model content

The technical problems to be solved in the utility model provides the test that a kind of single job can be finished thickness to silicon chip, thickness deviation, body resistivity data simultaneously, and easy to operate, stable, accurately, the silicon chip checkout equipment that service efficiency is high.

In order to solve the problems of the technologies described above, the technical solution of the utility model provides a kind of non-contact type silicon wafer thickness resistivity detection system, it is characterized in that: comprise test module, signal processing module links to each other with test module, and control module links to each other with signal processing module;

Test module comprises pedestal, the plummer that is used to place silicon chip is located at pedestal, the last capacitive transducer and the following capacitive transducer that are used to measure silicon wafer thickness are located at pedestal by the fixed mount of popping one's head in, and last capacitive transducer all links to each other with amplifying circuit with following capacitive transducer; The last eddy current sensor and the following eddy current sensor that are used to measure silicon chip resistivity also are located at pedestal by the fixed mount of popping one's head in, and last eddy current sensor all links to each other with oscillatory circuit with following eddy current sensor; The surveyed area of silicon chip is between last capacitive transducer and following capacitive transducer, simultaneously also between last eddy current sensor and following eddy current sensor on the plummer;

Signal processing module mixes also the secondary signal processing unit of Filtering Processing by the vortex field variable signal apart from voltage signal mixes and first signal processing unit of Filtering Processing and being used for will collect last eddy current sensor and following eddy current sensor of the last capacitive transducer that is used for collecting and following capacitive transducer and forms, amplifying circuit connects first signal processing unit, and oscillating circuit connects the secondary signal processing unit;

Control module comprises microprocessor, and mould/number is connected with microprocessor with the D/A switch processor, is used to show that the thickness of silicon chip and the LCD touch-screen of resistivity also are connected microprocessor.

Preferably, described plummer is provided with the position markers that is used for 125mm * 125mm, two kinds of specification silicon chips of 156mm * 156mm center aligning.

When a kind of non-contact type silicon wafer thickness resistivity detection system that the utility model provides was used, silicon chip was placed on the plummer, between upper and lower capacitive transducer, simultaneously also between upper and lower eddy current sensor.Control by microprocessor, utilize the meter of upper and lower capacitive transducer to calculate silicon wafer thickness, utilize the meter of upper and lower eddy current sensor to calculate silicon chip resistivity, only need single job just can realize thickness, thickness deviation and the resistivity of crystal silicon solar silicon chip are carried out the function of non-contact type test, and easy to operate, stable, accurate, the service efficiency height.

The blank of present domestic semiconductor detection has been filled up by the system that the utility model provides, only need single job just can carry out non-contact type test, have that antijamming capability is strong, adaptive capacity to environment is strong, failure rate is low, easy to operate, characteristics that maintenance cost is low thickness, variation in thickness and the resistivity of crystal silicon solar silicon chip.

Description of drawings

A kind of non-contact type silicon wafer thickness resistivity detection system structural drawing that Fig. 1 provides for the utility model;

A kind of non-contact type silicon wafer thickness resistivity detection system test flow chart that Fig. 2 provides for the utility model;

Fig. 3 is a thickness parameter reperformance test data drawing list;

Fig. 4 is a thickness parameter accuracy test data chart;

Fig. 5 is a resistance parameter reperformance test data drawing list;

Fig. 6 is a resistance parameter accuracy test data chart;

Description of reference numerals

The 1-test module; The last capacitive transducer of 111-; Capacitive transducer under the 112-; The last eddy current sensor of 121-; Eddy current sensor under the 122-; The 131-silicon chip; The 132-plummer; The 133-pedestal; The 141-fixed mount of popping one's head in; The 151-oscillatory circuit; The 152-amplifying circuit; The 2-signal processing module; 21-first signal processing unit; 22-secondary signal processing unit; The 3-control module; The 31-microprocessor; 33-mould/number and D/A switch processor; The 32-LCD touch-screen.

Embodiment

For the utility model is become apparent, now with a preferred embodiment, and conjunction with figs. is described in detail below.

A kind of non-contact type silicon wafer thickness resistivity detection system structural drawing that Fig. 1 provides for the utility model, described a kind of non-contact type silicon wafer thickness resistivity detection system comprises test module 1, signal processing module 2 and control module 3, test module 1 links to each other with signal processing module 2, and signal processing module 2 links to each other with control module 3.

Silicon chip 131 is crystal silicon solar silicon chips, is placed on the plummer 132 that is used to support silicon chip 131.The size of silicon chip 131 is generally 125mm * 125mm or 156mm * 156mm, also can be suitable for the silicon chip of other size if any specific demand.

Test module 1 comprises a pair of capacitive transducer that is used to measure silicon chip 131 thickness, comprises capacitive transducer 111 and following capacitive transducer 112, and is fixed on the probe fixed mount 141, and probe fixed mount 141 is fixed on the pedestal 133.By measuring the distance that upper and lower capacitive transducer surface and silicon chip 131 above and below capacitances can transform the distance that obtains capacitive transducer 111 and silicon chip 131 upper surfaces, following capacitive transducer 112 and silicon chip 131 lower surfaces.Upper and lower capacitive transducer all links to each other with amplifying circuit 152, amplifying circuit 152 give upper and lower capacitive transducer provide drive signal and sensor measurement to capacitance signal change into the voltage output signal.

Test module 1 also comprises a pair of eddy current sensor that is used to measure silicon chip 131 resistivity, comprise eddy current sensor 121 and following eddy current sensor 122, and be fixed on the probe fixed mount 141, upper and lower eddy current sensor all links to each other with oscillatory circuit 151, oscillatory circuit 151 offers upper and lower eddy current sensor oscillator signal, on silicon chip 131, produce the variation of vortex field thus, and convert current output signal to by oscillating circuit 151.

Measurement module 1 also comprises the plummer 132 that is used to support silicon chip 131, during measurement, silicon chip 131 is placed on the plummer 132, is useful on the position markers of conventional crystal silicon solar silicon chip 125mm * 125mm, two kinds of specification silicon chips of 156mm * 156mm center aligning on the plummer 132.Plummer 132 is fixed on the pedestal 133, and pedestal 133 is made up of aluminum alloy materials, has enough rigidity.When silicon chip 131 was placed on plummer 132, it was between last capacitive transducer 111 and following capacitive transducer 112, simultaneously also between last eddy current sensor 121 and following eddy current sensor 122.

Signal processing module 2 is made up of first signal processing unit 21 and secondary signal processing unit 22, the measured distance signal of measurement module 1 outputs to first signal processing unit, 21, the first signal processing units 21 mixing and signal is carried out Filtering Processing apart from voltage signal the last capacitive transducers 111 that collect and following capacitive transducer 112 by amplifying circuit 152.And measurement module 1 measured vortex field variable signal outputs to secondary signal processing unit 22 by oscillating circuit 151.

Control module 3 comprises microprocessor (MCU) 31, mould/number and D/A switch processor 33, and LCD touch-screen 32 and Control Software, control module 3 are carried out work such as signal conversion processes, data operation, data presentation by Control Software.

In conjunction with Fig. 2, the flow process of the utility model test crystal silicon solar silicon wafer thickness, resistivity and thickness deviation is as follows:

The first step: the surveyed area that silicon chip 131 is placed on plummer 132.

Second step: measure first distance A that goes up plane on capacitive transducer 111 surfaces and the silicon chip 131 by last capacitive transducer 111.

The 3rd step: by the second distance B of capacitive transducer 112 surfaces under capacitive transducer 112 is measured down with silicon chip 131 lower planes.

The 4th step: calculate by 3 pairs of silicon wafer thicknesses of control module.Computing formula:

Silicon wafer thickness=D-(A+B)

Wherein, D is known last capacitive transducer 111 and the fixed range between the following capacitive transducer 112.

The 5th step: by the variation of last eddy current sensor 121 and following eddy current sensor 122 measurement silicon chip surface vortex fields.

The 6th step: convert the variation of vortex field the variation of vortex flow to by signal processing unit 22, and convert conductivity to by control module 3.

The 7th step: control module 3 calculates the resistivity of silicon chip by conductivity that obtains and the silicon wafer thickness that measures before, and the thickness of silicon chip and resistivity are presented on the LCD touch-screen 32.The resistivity of silicon chip is calculated formula:

Resistivity=silicon wafer thickness/G

Wherein, G is the conductivity that measures.

The 8th step: if the thickness deviation of test silicon wafer is opened the thickness deviation computation schema.

The 9th step: after opening the thickness deviation test pattern, allow silicon chip 131 between last capacitive transducer 111 and following capacitive transducer 112, move, by control module 3 calculated thickness deviations.

The tenth step: show final test result.

After finishing test, silicon chip 131 is removed from plummer 132, next to be measured is repeated above testing procedure again.As long as test a slice silicon chip is probably 2.5 seconds.This shows that this test macro is fit to the testing requirement of solar battery sheet industry to the crystal silicon solar batteries sheet very much.

Fig. 3～Fig. 6 is the repeatability and the stability curve figure of this test macro, below these curve maps is done to explain in detail.

Fig. 3 is native system 10 test results of repetition to doing with a slice silicon chip, and this silicon wafer thickness value is demarcated by metering institute of country, and its error is less than ± 1 micron as can be seen.

Fig. 4 is the data plot that 10 different silicon chips of thickness is carried out thickness measuring, and the thickness of these 10 silicon chips is by between 150 microns～700 microns, and these silicon wafer thickness values are all demarcated and authentication by metering institute of country.The degree of agreement of actual value and test value as seen from Figure 4, wherein R2=1 represents to fit like a glove.

Fig. 5 is this test macro to resistivity is that same a slice silicon chip of 4.33 Ω .cm carries out test result 10 times, and the resistivity value of this silicon chip is demarcated and authentication by metering institute of country.As can be seen from the figure test error is less than 3%.

Fig. 6 is demarcated and the test data of 5 sheet resistivity prints on this test macro of authentication by country metering institute, the degree of agreement of actual value and test value as seen from Figure 6, and wherein R2=1 represents to fit like a glove.

In sum, this test macro is as long as single job just can be measured thickness, thickness deviation and the resistivity of silicon chip, and the accuracy of system and stability satisfy the requirement of current photovoltaic industry to testing apparatus fully.

Claims

1. non-contact type silicon wafer thickness resistivity detection system, it is characterized in that: comprise test module (1), signal processing module (2) links to each other with test module (1), and control module (3) links to each other with signal processing module (2);

Test module (1) comprises pedestal (133), the plummer (132) that is used to place silicon chip (131) is located at pedestal (133), the last capacitive transducer (111) and the following capacitive transducer (112) that are used to measure silicon chip (131) thickness are located at pedestal (133) by probe fixed mount (141), and last capacitive transducer (111) all links to each other with amplifying circuit (152) with following capacitive transducer (112); The last eddy current sensor (121) and the following eddy current sensor (122) that are used to measure silicon chip (131) resistivity also are located at pedestal (133) by probe fixed mount (141), and last eddy current sensor (121) all links to each other with oscillatory circuit (151) with following eddy current sensor (122); The surveyed area that plummer (132) is gone up silicon chip (131) is positioned between capacitive transducer (111) and the following capacitive transducer (112), also is positioned between eddy current sensor (121) and the following eddy current sensor (122) simultaneously;

Signal processing module (2) mixes also the secondary signal processing unit (22) of Filtering Processing by the vortex field variable signal apart from voltage signal mixes and first signal processing unit (21) of Filtering Processing and being used for will collect last eddy current sensor (121) and following eddy current sensor (122) of the last capacitive transducer (111) that is used for collecting and following capacitive transducer (112) and forms, amplifying circuit (152) connects first signal processing unit (21), and oscillating circuit (151) connects secondary signal processing unit (22);

Control module (3) comprises microprocessor (31), and mould/number is connected with microprocessor (31) with D/A switch processor (33), is used to show that the thickness of silicon chip and the LCD touch-screen (32) of resistivity also are connected microprocessor (31).

2. a kind of non-contact type silicon wafer thickness resistivity detection system as claimed in claim 1 is characterized in that: described plummer (132) is provided with the position markers that is used for 125mm * 125mm, two kinds of specification silicon chips of 156mm * 156mm center aligning.