Calibration method of CIS probe card measurement equipment

Abstract

The invention relates to a calibration method of CIS probe card measuring equipment, which comprises the following steps: step 1, before testing, debugging a product bracket for fixing a product to be tested to a preset height; 2, obtaining a plurality of calibration blocks consistent with the sizes of the to-be-tested products respectively, obtaining a plurality of calibration seats matched with the to-be-tested products respectively, and installing one calibration block in the product support through the corresponding calibration seat; 3, a light source is arranged in front of the calibration block, a light sensor is arranged behind the calibration block, and the horizontal angle and the vertical angle of the light sensor are adjusted, so that the planes where the light source, the calibration block and the light sensor are located are parallel; 4, dismounting the calibration block, replacing the calibration block with a corresponding product to be tested, and starting to test; and 5, after the test is completed, compensating the output value of the optical sensor based on a compensation algorithm to obtain a calibration result. Deviation of parameters such as light intensity and illumination of the light source at different positions can be eliminated, and optical parameter detection of the lens module is achieved.

Description

Technical Field

[0001] The present invention relates to the field of chip detection technology, and in particular to a calibration method for CIS probe card measurement equipment. Background Art

[0002] With the development of chip manufacturing technology, CIS sensors are increasingly used in automobiles, mobile phones, security and other fields. They directly capture images or light signals. As an important means of monitoring and intercepting the quality of chip shipments, wafer-level CIS chip testing is gaining more and more attention. In the CIS probe card, the lens module plays the role of transmitting light, and its performance has a direct impact on the test results of the CIS chip. The lens module of the CIS probe card is composed of multiple single-mode components. The single-mode component is composed of other important optical components such as lenses (multiple lenses). Traditional detection methods can only detect the transmittance of a single lens in a single-mode component. The size of the lens module is much larger than that of the single-mode component. Therefore, the difference in light source when detecting the lens module will cause measurement deviation, thereby affecting the measurement results and making the test results unreliable.

[0003] Therefore, how to provide a calibration method for a CIS probe card measurement device capable of detecting optical parameters of a lens module is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0004] The present invention provides a calibration method for CIS probe card measurement equipment to solve the above technical problems.

[0005] To solve the above technical problems, the present invention provides a calibration method for a CIS probe card measurement device, comprising the following steps:

[0006] Step 1: Before testing, adjust the product stand used to fix the product to be tested to the preset height;

[0007] Step 2: Obtain multiple calibration blocks that are consistent with the sizes of the various products to be tested, obtain multiple calibration seats that are respectively adapted to the various products to be tested, and install a calibration block in the product holder through the corresponding calibration seat;

[0008] Step 3: Setting a light source in front of the calibration block and a light sensor behind the calibration block, and adjusting the horizontal and vertical angles of the light sensor so that the planes of the light source, calibration block, and light sensor are parallel;

[0009] Step 4: Remove the calibration block, replace it with the corresponding product to be tested, and start testing;

[0010] Step 5: After the test is completed, the output value of the light sensor is compensated based on the compensation algorithm to obtain a calibration result.

[0011] Preferably, in step 3, a calibration table is set to detect the distance and flatness between the light sensor and the calibration block, the position of the calibration table is changed to obtain several sets of adjustment data, and the horizontal and vertical angles of the light sensor are adjusted based on the adjustment data.

[0012] Preferably, the adjustment data obtained by detection are 2 or 3 groups.

[0013] Preferably, the compensation algorithm comprises the following steps:

[0014] Step 51: Use a lens module with the same size as the product to be tested for testing, with only the light tube assembled in the lens module;

[0015] Step 52: The light source sets multiple specific monitoring values, and finds the parameter value range required by the corresponding product to be tested, with the minimum value set as min and the maximum value set as max;

[0016] Step 53: Between the minimum value min and the maximum value max, the light source is measured once every time a step length is increased, and the optical parameter measurement value of each light tube in the lens module is recorded;

[0017] Step 54: Calculate the average optical parameter of each light cylinder in each measurement, and compensate the output value of the light sensor based on the difference between the average optical parameter and the measured optical parameter value of the corresponding light cylinder.

[0018] Preferably, the specific monitoring points include 100lx, 200lx, 300lx, 400lx, 500lx, ..., 10000lx.

[0019] Preferably, the step length is 5lx.

[0020] Preferably, the calibration result after compensation is x+(Bb), where x is the output value corresponding to a certain light tube output by the light sensor, b is the optical parameter measurement value closest to x in multiple measurements, and B is the average optical parameter of each light tube in the measurement corresponding to b.

[0021] Preferably, the method for finding the optical parameter measurement value closest to x is: calculating the absolute value of the difference between the optical parameter measurement value of the light tube in each measurement and x, and the optical parameter measurement value of the light tube in the measurement corresponding to the minimum absolute value is b.

[0022] Preferably, based on the measurement and calculation results of steps 53 and 54, a reading table is formed, the horizontal axis of the reading table corresponds to multiple measurements from the minimum value min to the maximum value max, and the vertical axis of the reading table corresponds to the optical parameter measurement values ​​corresponding to each light tube in each measurement and the average optical parameter of each light tube in the measurement.

[0023] Preferably, when replacing a product to be tested of the same model, the current product to be tested is removed from the calibration seat, the next product to be tested is installed and tested; when replacing a product to be tested of a different model, the current product to be tested and the calibration seat are removed, the calibration seat matching the next product to be tested is replaced, and then the next product to be tested is installed and tested.

[0024] Compared with the prior art, the calibration method of the CIS probe card measurement equipment provided by the present invention has the following advantages:

[0025] 1. The calibration method provided by the present invention can eliminate the deviation of the optical parameters of the light source at different positions and realize the optical parameter detection of the lens module;

[0026] 2. The present invention uses a calibration block for early debugging, and replaces the corresponding product to be tested after debugging is completed to avoid damage to the product to be tested;

[0027] 3. The present invention provides a variety of different types of calibration blocks and calibration seats. When the product to be tested needs to be replaced, the corresponding calibration block and / or calibration seat can be directly replaced according to the needs, thereby improving the detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A flowchart of a calibration method for a CIS probe card measurement device according to one embodiment of the present invention;

[0029] Figure 2 Schematic diagram of an application device for a calibration method of a CIS probe card measurement device in one embodiment of the present invention.

[0030] In the figure: 10 - calibration block, 11 - product holder, 12 - calibration base, 20 - light source, 30 - light sensor, 40 - calibration table. DETAILED DESCRIPTION

[0031] In order to describe the technical solution of the above invention in more detail, specific embodiments are listed below to demonstrate the technical effects; it should be emphasized that these embodiments are used to illustrate the present invention and are not used to limit the scope of the present invention.

[0032] The present invention provides a calibration method for a CIS probe card measuring device, such as Figure 1 and Figure 2 As shown, the following steps are included:

[0033] Step 1: Before testing, adjust the product stand 11 used to hold the product to be tested (not shown) to a preset height;

[0034] Step 2: Obtain multiple calibration blocks 10 that are consistent with the sizes of the various products to be tested, obtain multiple calibration seats 12 that are respectively adapted to the various products to be tested, and install a calibration block 10 in the product bracket 11 through the corresponding calibration seat 12;

[0035] Step 3: A light source 20 is provided in front of the calibration block 10, and a light sensor 30 is provided behind the calibration block 10. The horizontal and vertical angles of the light sensor 30 are adjusted so that the planes on which the light source 20, the calibration block 10, and the light sensor 30 are located are parallel.

[0036] Step 4: Remove the calibration block 10 and replace it with the corresponding product to be tested, and start testing optical parameters such as illuminance, brightness and imaging distribution;

[0037] Step 5: After the test is completed, the output value of the optical sensor 30 is compensated based on the compensation algorithm to obtain a calibration result.

[0038] The present invention uses the calibration block 10 for preliminary debugging, and replaces the corresponding product to be tested after debugging is completed to avoid damage to the product to be tested; the calibration method provided by the present invention can eliminate the deviation of the optical parameters of the light source 20 at different positions and realize the optical parameter detection of the lens module.

[0039] In some embodiments, in step 3, a calibration table 40 is set to detect the distance and flatness between the light sensor 30 and the calibration block 10, and the position of the calibration table 40 is changed to obtain several groups (in this embodiment, 2 groups or 3 groups) of adjustment data, and the horizontal and vertical angles of the light sensor 30 are adjusted based on the adjustment data.

[0040] In some embodiments, the compensation algorithm comprises the following steps:

[0041] Step 51: Use a lens module with the same size as the product to be tested for testing, and only assemble a light tube in the lens module to reduce interference with the testing process.

[0042] Step 52: This application takes the compensation illumination as an example, and sets multiple specific monitoring values ​​for the light source, such as 100lx, 200lx, 300lx, 400lx, 500lx, ..., 10000lx, and finds the corresponding parameter value range required for the product to be tested. Taking 100lx to 200lx as an example, the minimum value 100lx is set as min, and the maximum value 200lx is set as max.

[0043] Step 53: Between the minimum value min and the maximum value max, the light source is measured once every time a step length is increased (in this embodiment, a step length is 5lx), and the optical parameter measurement value of each light tube in the lens module is recorded.

[0044] Step 54: Calculate the average optical parameter of each light cylinder in each measurement, and compensate the output value of the optical sensor 30 based on the difference between the average optical parameter and the measured optical parameter value of the corresponding light cylinder.

[0045] In some embodiments, a reading table is formed based on the measurement and calculation results of steps 53 and 54, see Table 1. The horizontal axis of the reading table corresponds to multiple measurements from the minimum value min to the maximum value max, and the vertical axis of the reading table corresponds to the optical parameter measurement values ​​corresponding to each light tube in each measurement and the average value of the optical parameters of each light tube in the measurement, so that the calibration result can be quickly obtained by reading the table.

[0046] Table 1 Reading table

[0047] Light tube\light source min min+5 min+10 … … max 1 a1 b1 c1 … … M1 2 a2 b2 c2 … … M2 3 a3 b3 c3 … … … 4 a4 b4 c4 … … … 5 … … … … … … 6 … … … … … … average value A B C … … Mavg

[0048] Specifically, the compensated calibration result is x + (Bb), where x is the output value corresponding to a particular light cylinder output by the light sensor 30, b is the optical parameter measurement value closest to x during multiple measurements, and B is the average optical parameter value of each light cylinder in the measurement corresponding to b. The calibration result can be obtained by looking up the reading table. For example, if x is the output value corresponding to the second light cylinder output by the light sensor 30, the optical parameter measurement value closest to x is found in row 2 on the vertical axis. If the value found is b2, and the average value of this column is B, then the final compensated calibration result is x + (B - b2). Alternatively, if x is the output value corresponding to the fourth light cylinder output by the light sensor 30, the optical parameter measurement value closest to x is found in row 4 on the vertical axis. If the value found is c4, and the average value of this column is C, then the final compensated calibration result is x + (C - c4).

[0049] In some embodiments, the method for finding the optical parameter measurement value closest to x is to calculate the absolute value of the difference between the optical parameter measurement value of the light tube in each measurement and x. The optical parameter measurement value of the light tube corresponding to the minimum absolute value is b. Using the above example again, the optical parameter measurement value closest to x is obtained by calculating the minimum value among |x-a²|, |x-b²|, |x-c²|, and so on.

[0050] In some embodiments, when replacing a product to be tested of the same model, the current product to be tested can be removed from the calibration seat 12, and the next product to be tested or calibration block 10 can be installed and tested; when replacing a product to be tested of a different model, the current product to be tested and the calibration seat 12 can be removed, and a calibration seat 12 that matches the next product to be tested can be replaced, and then the next product to be tested or calibration block 10 can be installed and tested. The present invention provides a plurality of different models of calibration blocks 10 and calibration seats 12. When the product to be tested needs to be replaced, the corresponding calibration block 10 and / or calibration seat 12 can be directly replaced according to the needs, thereby improving the detection efficiency.

[0051] In summary, the calibration method of the CIS probe card measurement device provided by the present invention includes the following steps:

[0052] Step 1: Before testing, adjust the product holder 11 used to fix the product to be tested to a preset height; Step 2: Obtain multiple calibration blocks 10 that are consistent with the sizes of each type of product to be tested, obtain multiple calibration seats 12 that are respectively adapted to each type of product to be tested, and install a calibration block 10 in the product holder 11 through the corresponding calibration seat 12; Step 3: Set a light source 20 in front of the calibration block 10, set a light sensor 30 behind the calibration block 10, and adjust the horizontal and vertical angles of the light sensor 30 so that the planes of the light source 20, calibration block 10 and light sensor 30 are parallel; Step 4: Remove the calibration block 10, replace it with the corresponding product to be tested, and start testing; Step 5: After the test is completed, compensate the output value of the light sensor 30 based on the compensation algorithm to obtain the calibration result. The present invention uses the calibration block 10 for preliminary debugging, and replaces the corresponding product to be tested after debugging is completed to avoid damage to the product to be tested; the calibration method provided by the present invention can eliminate the deviation of the optical parameters of the light source 20 at different positions and realize the optical parameter detection of the lens module.

[0053] Obviously, those skilled in the art may make various changes and modifications to the invention without departing from the spirit and scope of the invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A calibration method for a CIS probe card measurement device, characterized in that: The steps include: Step 1: Before testing, adjust the product stand used to fix the product to be tested to the preset height; Step 2: Obtain multiple calibration blocks that are consistent with the sizes of the various products to be tested, obtain multiple calibration seats that are respectively adapted to the various products to be tested, and install a calibration block in the product holder through the corresponding calibration seat; Step 3: Setting a light source in front of the calibration block and a light sensor behind the calibration block, and adjusting the horizontal and vertical angles of the light sensor so that the planes of the light source, calibration block, and light sensor are parallel; Step 4: Remove the calibration block, replace it with the corresponding product to be tested, and start testing; Step 5: After the test is completed, the output value of the light sensor is compensated based on the compensation algorithm to obtain a calibration result.

2. The calibration method of the CIS probe card measurement device according to claim 1, wherein: In step 3, a calibration table is set to detect the distance and flatness between the optical sensor and the calibration block, the position of the calibration table is changed to obtain several sets of adjustment data, and the horizontal and vertical angles of the optical sensor are adjusted based on the adjustment data.

3. The calibration method of the CIS probe card measurement device according to claim 2, wherein: The adjustment data obtained by detection are 2 or 3 groups.

4. The calibration method of the CIS probe card measurement device according to claim 1, wherein: The compensation algorithm comprises the following steps: Step 51: Use a lens module with the same size as the product to be tested for testing, with only the light tube assembled in the lens module; Step 52: The light source sets multiple specific monitoring values, and finds the parameter value range required by the corresponding product to be tested, with the minimum value set as min and the maximum value set as max; Step 53: Between the minimum value min and the maximum value max, the light source is measured once every time a step length is increased, and the optical parameter measurement value of each light tube in the lens module is recorded; Step 54: Calculate the average optical parameter of each light cylinder in each measurement, and compensate the output value of the light sensor based on the difference between the average optical parameter and the measured optical parameter value of the corresponding light cylinder.

5. The calibration method of the CIS probe card measurement device according to claim 4, wherein: The specific monitoring points include 100lx, 200lx, 300lx, 400lx, 500lx, ..., 10000lx.

6. The calibration method of the CIS probe card measurement equipment according to claim 5, wherein: The step size is 5lx.

7. The calibration method of the CIS probe card measurement equipment according to claim 4, wherein: The calibration result after compensation is x + (Bb), where x is the output value corresponding to a light tube output by the optical sensor, b is the optical parameter measurement value closest to x in multiple measurements, and B is the average optical parameter value of each light tube in the measurement corresponding to b.

8. The calibration method of the CIS probe card measurement equipment according to claim 7, wherein: The method for finding the optical parameter measurement value closest to x is: calculate the absolute value of the difference between the optical parameter measurement value of the light tube in each measurement and x, and the optical parameter measurement value of the light tube in the measurement corresponding to the minimum absolute value is b.

9. The calibration method of the CIS probe card measurement equipment according to claim 4, wherein: Based on the measurement and calculation results of steps 53 and 54, a reading table is formed, in which the horizontal axis of the reading table corresponds to multiple measurements from the minimum value min to the maximum value max, and the vertical axis of the reading table corresponds to the optical parameter measurement values ​​corresponding to each light tube in each measurement and the average optical parameter of each light tube in the measurement.

10. The calibration method of the CIS probe card measurement equipment according to claim 1, wherein: When replacing a product to be tested of the same model, remove the current product to be tested from the calibration seat, install the next product to be tested and perform the test; when replacing a product to be tested of a different model, remove the current product to be tested and the calibration seat, replace it with a calibration seat that matches the next product to be tested, and then install the next product to be tested and perform the test.

Images