A detection chip and a detection system

Abstract

The present application discloses a detection chip, characterized in that the detection chip is embedded in a semiconductor wafer body and is used for performing photoluminescence testing. The detection chip includes: a plurality of quantum well intermixing regions and non-quantum well intermixing regions arranged periodically or randomly, wherein the particle doping in the quantum well intermixing regions is the same as the particle doping in the quantum well doping layer contained in the semiconductor wafer body. Laser beams are received by the plurality of quantum well intermixing regions to generate photoluminescence reactions, and interference occurs between the light rays emitted by the photoluminescence of the plurality of quantum well intermixing regions, so that the signal intensity of the wavelength spectrum line emitted by the detection chip is enhanced. The blue shift of the wavelength of the detection chip can be measured by using a conventional spectrometer, and the anti-COD characteristic of the semiconductor wafer can be quickly judged.

Description

Technical Field

[0001] The present application relates to the field of lasers, and particularly to a detection chip and a detection system. Background Art

[0002] Due to advantages such as small size, high efficiency, long life, and wide wavelength coverage range, semiconductor lasers have been widely used in fields such as industry, medical treatment, and beauty in recent years. In the prior art, semiconductor lasers are prone to COMD (Catastrophic Optical Mirror Damage) on the light-emitting surface. COMD is one of the important reasons restricting the high-power light output and reliability of semiconductor lasers; reducing or eliminating the light absorption on the light-emitting surface can effectively increase the threshold power of COMD occurrence.

[0003] To reduce the light absorption on the light-emitting surface of a semiconductor laser, a common method is to increase the bandgap width of the semiconductor material at the light-emitting surface. In the prior art, generally, quantum well intermixing (QWI) technology is used to increase the bandgap width of the quantum well material at the light-emitting surface of the semiconductor laser, while the bandgap width of the quantum well material in other regions, especially below the current injection region, remains unchanged, so that the photoluminescence (PL) of the quantum well material at the light-emitting surface of the semiconductor laser is blue-shifted relative to the laser wavelength of the laser, or rather, the blue-shift situation of the photoluminescence wavelength is an important judgment basis for the quantum well intermixing of the semiconductor laser.

[0004] The photoluminescence intensity of conventional semiconductor laser quantum well intermixing is relatively weak, and a larger irradiation area or high-power laser irradiation is required to generate a sufficient intensity of spectral test signal, resulting in that the produced semiconductor lasers need to sacrifice a relatively large test area, and at the same time, the test area cannot be used for the final product. Therefore, currently, the photoluminescence of semiconductor lasers is only used for epitaxial wafer monitoring. In the chip process, blank wafers are often used for measurement after plating and heat treatment, and it is not used on the actual production semiconductor wafers. Summary of the Invention

[0005] The present application provides a detection chip and a detection system to solve the technical problems in the prior art.

[0006] To solve the above technical problems, the present application provides a detection chip, which is embedded in a semiconductor wafer body and is used for photoluminescence testing. The detection chip includes:

[0007] A plurality of periodically arranged or randomly arranged quantum well intermixing regions and non-quantum well intermixing regions, wherein the particle doping in the quantum well intermixing regions is the same as the particle doping in the quantum well doping layer included in the semiconductor wafer body.

[0008] In one embodiment, the quantum well intermixing region is a test line, and the test lines and the non-quantum well intermixing regions are arranged alternately.

[0009] In one embodiment, the quantum well intermixing regions are linearly arranged, and the distances between any adjacent quantum well intermixing regions are equal or unequal.

[0010] In one embodiment, the quantum well intermixing region is a test pattern, the non-quantum well intermixing regions are arranged around the test pattern, and multiple test patterns are arranged in a matrix.

[0011] In one embodiment, the test pattern includes at least one of a square, a circle, a triangle, or a polygon.

[0012] In one embodiment, the total area of multiple quantum well intermixing regions is 0.5 mm 2 -1.5 mm 2 .

[0013] In one embodiment, the ratio range of the total area of multiple quantum well intermixing regions to the total area of multiple non-quantum well intermixing regions is 5-10.

[0014] In one embodiment, the distance between the surface of the quantum well intermixing region and the surface of the non-quantum well intermixing region is less than 2 μm.

[0015] In one embodiment, the detection chip further includes at least one alignment mark for alignment.

[0016] To solve the above technical problems, the present application further provides a detection system for testing the detection chip as described above, including:

[0017] A semiconductor workbench;

[0018] A laser light source for generating a laser beam, the laser beam irradiating the detection chip carried on the semiconductor workbench to cause a photoluminescence reaction of the detection chip and emit light;

[0019] A spectrometer that receives the light through an optical processing system, detects the light, and measures the wavelength spectrum of the detection chip;

[0020] An imaging system connected to the spectrometer through a USB data cable, imaging the wavelength spectrum, and displaying the blue shift of the wavelength spectrum to determine the anti-COD characteristics of the semiconductor wafer.

[0021] The beneficial effects of the present application are as follows: Different from the prior art, the detection chip of the present application includes periodically arranged or randomly arranged quantum well intermixing regions and non-quantum well intermixing regions. Multiple quantum well intermixing regions receive laser beams to generate photoluminescence reactions. Interference occurs between the light rays emitted by the photoluminescence of multiple said quantum well intermixing regions, so that the signal intensity of the wavelength spectrum line emitted by the detection chip is enhanced. The blue shift of the wavelength of the detection chip can be measured using a conventional spectrometer, quickly realizing the judgment of the anti-COD characteristics of the semiconductor wafer. The operation is convenient, and there is no need to use other expensive equipment for detection, which can improve the detection efficiency and production capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 is a schematic plan view of an embodiment of a semiconductor wafer of the present application;

[0024] Figure 2 is a schematic plan view of an embodiment of the detection chip of the present application;

[0025] Figure 3 is a schematic plan view of another embodiment of the detection chip of the present application;

[0026] Figure 4 is a schematic plan view of another embodiment of the detection chip of the present application;

[0027] Figure 5 is a schematic plan view of another embodiment of the detection chip of the present application;

[0028] Figure 6 is a schematic cross-sectional view of an embodiment of the detection chip of the present application;

[0029] Figure 7 is a schematic cross-sectional view of another embodiment of the detection chip of the present application;

[0030] Figure 8 is a schematic cross-sectional view of another embodiment of the detection chip of the present application;

[0031] Figure 9 is a schematic structural view of an embodiment of the detection system of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] To enable those skilled in the art to better understand the technical solution of the present application, the detection system and detection chip provided by the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It can be understood that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope protected by the present application.

[0033] The terms "first", "second", etc. in the present application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0034] Please refer to Figure 1 , Figure 1 is a schematic plan view of an embodiment of a semiconductor wafer of the present application. A detection chip 12 is embedded in the semiconductor wafer 11. A plurality of laser resonators and cutting lines are formed on the semiconductor wafer 11. After cutting or splitting, N laser chips 13 of the same or different sizes can be formed. The detection chip 12 further includes at least one alignment mark 14 for alignment. Further, the alignment mark 14 can be aligned with the alignment mark of the semiconductor wafer 11 when the detection chip 12 is embedded in the semiconductor wafer 11, so that the detection chip 12 can be quickly embedded in the correct position of the semiconductor wafer 11. The alignment mark 14 can also be used when the detection device performs detection, and quickly locates to the area of the detection chip 12 for detection, improving the detection efficiency and detection accuracy.

[0035] In the prior art, it is necessary to further perform a photoluminescence PL test on the cut laser chip 13 to measure the wavelength blue shift of the QWI processed by thermal diffusion, ion implantation or strain layer treatment, so as to further judge the anti-COD characteristics of the laser chip 13. In this embodiment, by directly performing a photoluminescence test on the detection chip 12 of the semiconductor wafer 11, the detection result of the anti-COD characteristics of the laser chip 13 related to this semiconductor wafer 11 can be obtained. That is to say, only by one inspection, the average anti-COD characteristics of the N laser chips 13 on the semiconductor wafer 11 can be obtained, without separately detecting each laser chip 13, which can effectively improve the detection efficiency, simplify the preparation process of the laser chip 13, and improve the production capacity.

[0036] Further refer to Figure 2 , Figure 2It is a first planar schematic diagram of an embodiment of the detection chip of the present application. The detection chip 12 includes a quantum well intermixing region 122 and a non-quantum well intermixing region 121. Among them, the quantum well intermixing region 122 is the same as the QWI obtained by thermal diffusion, ion implantation or strain layer treatment of the entire semiconductor wafer 11. That is, the detection chip 12 is formed by splicing the QWI obtained by subjecting the semiconductor wafer 11 to thermal diffusion, ion implantation or strain layer treatment. The epitaxial structure of each quantum well intermixing region 122 of the detection chip 12 is the same as that of the QWI of the semiconductor wafer 11. By measuring the photoluminescence of the quantum well intermixing region 122 of the detection chip 12, the anti-COD ability of the laser chip 13 included in the entire semiconductor wafer 11 can be judged through the blue shift of the wavelength.

[0037] Optionally, the quantum well intermixing region 122 of the detection chip 12 can be a periodically arranged test line or test pattern, or the quantum well intermixing region 122 of the detection chip 12 can be a non-periodically arranged test line and test pattern. In the present application, by arranging the quantum well intermixing region 122 periodically or non-periodically, the total area of the detection region is increased. At the same time, the emitted light rays of multiple quantum well intermixing regions 122 interfere with each other, enhancing the signal intensity of the photoluminescence wavelength spectrum of the detection chip 12, quickly detecting the blue shift of the wavelength of the QWI of the semiconductor wafer 11, and then being used to judge the anti-COD ability of the laser chip 13 included in the semiconductor wafer 11.

[0038] The detection chip 12 will be described below with reference to specific embodiments.

[0039] As Figure 2 shown, the quantum well intermixing region 122 is a test line, the quantum well intermixing region 122 and the non-quantum well intermixing region 121 are arranged alternately and periodically, and the quantum well intermixing region 122 is linearly arranged. The distance between any two adjacent linearly arranged quantum well intermixing regions 122 is equal, that is, the widths of all non-quantum well intermixing regions 121 are equal. Among them, the width d1 of the quantum well intermixing region 122 is much smaller than the width d2 of the non-quantum well intermixing region 121, so that the area of the quantum well intermixing region 122 is much smaller than the area of the non-quantum well intermixing region 121. Among them, the width d1 of the quantum well intermixing region 122 is 10 μm, and the width d2 of the non-quantum well intermixing region 121 is 90 μm. In the present application, by arranging the quantum well intermixing region 122 periodically or non-periodically, the total area of the detection region is increased. At the same time, the emitted light rays of multiple quantum well intermixing regions 122 interfere with each other, enhancing the signal intensity of the photoluminescence wavelength spectrum of the detection chip 12, quickly detecting the blue shift of the wavelength of the QWI of the semiconductor wafer 11, and then being used to judge the anti-COD ability of the laser chip 13 included in the semiconductor wafer 11.

[0040] Further referring to Figure 3 ,Figure 3 It is a plan view of another embodiment of the detection chip of the present application. Different from the above embodiment, the distances between any adjacent quantum well mixing regions 122 in this embodiment are not equal, and multiple quantum well mixing regions 122 are regularly distributed. As Figure 3 shown, the distance between the nth quantum well mixing region 122 and the (n + 1)th quantum well mixing region 122 is d3, and the distance between the (n + 1)th quantum well mixing region 122 and the (n + 2)th quantum well mixing region 122 is d4, where d3 is greater than d4, and n is 1, 3, 5. Optionally, in other embodiments, the number of quantum well mixing regions 122 can be 8, 10, 12, etc. By arranging the quantum well mixing regions 122 periodically or non-periodically, the present application increases the total area of the detection region. At the same time, the outgoing light rays of multiple quantum well mixing regions 122 interfere with each other to enhance the signal intensity of the photoluminescence wavelength spectrum of the detection chip 12, quickly detect the wavelength blue shift of the QWI of the semiconductor wafer 11, and then use it to judge the anti-COD ability of the laser chip 13 included in the semiconductor wafer 11.

[0041] Further referring to Figure 4 , Figure 4 It is a plan view of another embodiment of the detection chip of the present application. As Figure 4 shown, the quantum well mixing region 122 is a test pattern, and the non-quantum well mixing region 121 is arranged around the quantum well mixing region 122, and multiple quantum well mixing regions 122 are arranged in a matrix. Among them, the quantum well mixing region 122 is square. Optionally, in other embodiments, the quantum well mixing region 122 can be circular, triangular or polygonal, etc. The total area of multiple quantum well mixing regions 122 is S1, and the range of S1 is 0.5 mm 2 -1.5 mm 2 . Optionally, S1 can be 1 mm 2 . The total area of the non-detection region 121 is S2, and the ratio range of S1 to S2 is 5 - 10. By arranging the quantum well mixing regions 122 periodically or non-periodically, the present application increases the total area of the detection region. At the same time, the outgoing light rays of multiple quantum well mixing regions 122 interfere with each other to enhance the signal intensity of the photoluminescence wavelength spectrum of the detection chip 12, quickly detect the wavelength blue shift of the QWI of the semiconductor wafer 11, and then use it to judge the anti-COD ability of the laser chip 13 included in the semiconductor wafer 11.

[0042] Further referring to Figure 5 , Figure 5 It is a plan view of another embodiment of the detection chip of the present application. Different from the above embodiment, the quantum well mixing region 122 in this embodiment includes a triangular quantum well mixing region 122 and a circular quantum well mixing region 122. As Figure 5As shown, the triangular quantum well mixing regions 122 and the circular quantum well mixing regions 122 are arranged alternately, such that the quantum well mixing regions 122 are regularly arranged in a periodic pattern. Optionally, in other embodiments, the quantum well mixing regions 122 may be formed by combining any two of a circle, a triangle, or a polygon, such as a circle and a rectangle, a triangle and a rectangle, etc.

[0043] In the prior art, the area of the QWI region on the laser chip is small, usually 10μm 2 , and a microPL instrument needs to be used for detecting a small area. The microPL instrument is relatively expensive and the operation is relatively complex, which is not conducive to the actual production requirements; on the other hand, the photoluminescence intensity of the QWI is weak, and a larger irradiation area or enhanced laser power needs to be used, resulting in damage to the semiconductor wafer 11 located in the detection area, reducing the output and increasing the production cost. In this application, by arranging the quantum well mixing regions 122 periodically or aperiodically, the total area of the detection region is increased. At the same time, the outgoing light rays of multiple quantum well mixing regions 122 interfere with each other to enhance the signal intensity of the photoluminescence wavelength spectrum of the detection chip 12, quickly detecting the wavelength blue shift of the QWI of the semiconductor wafer 11, and then used to judge the anti-COD ability of the laser chip 13 included in the semiconductor wafer 11.

[0044] Further referring to Figures 6 - 8 , Figure 6 is a schematic cross-sectional view of an embodiment of the detection chip of this application, Figure 7 is a schematic plan view of a cross-section of another embodiment of the detection chip of this application, Figure 8 is a schematic cross-sectional view of another embodiment of the detection chip of this application.

[0045] The distance between the surface of the quantum well mixing region 122 and the surface of the non-detection region 121 is less than 2μm. Taking the Figure 2 linear quantum well mixing region 122 as an example. In other embodiments, the distance between the surface of the quantum well mixing region 122 and the surface of the non-quantum well mixing region 121 is less than 2μm.

[0046] Such as Figure 6 shown, the distance between the surface of the linear quantum well mixing region 122 and the surface of the non-quantum well mixing region 121 is h1, and h1 is less than 2μm, that is, the range of h1 is 0μm - 2μm. As Figure 7 shown, the distance between the surface of the linear quantum well mixing region 122 and the surface of the non-quantum well mixing region 121 is h2, and h2 is less than 2μm, that is, the range of h2 is 0μm - 2μm.

[0047] Optionally, when h1 or h2 is 0μm, as Figure 8As shown, the distance between the surface of the linear quantum well mixing region 122 and the surface of the non-quantum well mixing region 121 is 0 μm, that is, the surface of the linear quantum well mixing region 122 is exactly flush with the surface of the non-quantum well mixing region 121.

[0048] In actual production, due to operation errors or equipment errors, there are deviations in the splicing of the surfaces of the quantum well mixing region 122 and the non-quantum well mixing region 121. In this application, the error value of the distance between the surface of the quantum well mixing region 122 and the surface of the non-quantum well mixing region 121 is set to 2 μm. As long as this condition is met, it is convenient to screen the detection chip 12.

[0049] Please refer to Figure 9 , Figure 9 which is a schematic structural diagram of an embodiment of the detection system of this application. As Figure 9 shown, the detection system 1 includes a laser light source 20, an optical processing system 30, a spectrometer 40, an imaging system 50, a USB data cable 60, and a semiconductor workbench 70. The optical processing system 30 includes an optical collector 31 and an optical waveguide 32. Among them, the imaging system 50 is a computer with data processing software.

[0050] The semiconductor wafer 11 is carried on the semiconductor workbench 70. The laser light source 20 generates a laser beam and irradiates the detection chip 12 on the semiconductor wafer 11. The detection chip 12 in the semiconductor wafer 11 receives the laser beam to generate a photoluminescence reaction and emits light outward. The optical collector 31 collects the light emitted by the detection chip 12, and the optical waveguide 32 transmits the light to the spectrometer 40. The spectrometer 40 detects the collected light and measures the wavelength spectrum of the detection chip 12. The imaging system 50 is connected to the spectrometer 40 through the USB data cable 60, images the wavelength spectrum data obtained from the spectrometer 40, and displays the blue shift of the wavelength spectrum through a display screen to determine the anti-COD characteristics of the semiconductor wafer 11.

[0051] Optionally, in other embodiments, other connection lines with data transmission functions can be selected to connect the imaging system 50 and the spectrometer 40.

[0052] Among them, COD (catastrophic optical damage) may include COBD (catastrophic optical body damage) or COMD (catastrophic optical mirror damage). COBD is mainly caused by the damage of the internal structure of the semiconductor wafer 11, while COMD is mainly caused by the damage of the mirror surface of the optical resonance cavity of the semiconductor component.

[0053] Different from the prior art in which an empty chip is used, measured after plating and heat treatment, in this embodiment, the detection chip 12 is embedded in the semiconductor wafer 11, and the detection chip 12 is used to receive a laser beam to generate a photoluminescence reaction, so as to realize the detection of the anti-COD characteristic of the semiconductor wafer 11. There is no need to use other detection equipment to detect the presence of COMD, which effectively improves the detection efficiency and reduces the detection cost. Before the semiconductor wafer 11 is cut to form the laser chip 13, the anti-COD characteristic of the semiconductor wafer 11 is detected in this embodiment, so that problems can be found in time, the process of the semiconductor wafer 11 can be adjusted, the quality of the semiconductor wafer 11 can be improved, the scrap rate can be reduced, and the production cost can be lowered.

[0054] The above are only the embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied to other related technical fields, shall be similarly included in the patent protection scope of the present application.

Claims

1. A detection chip, characterized in that, The detection chip is embedded in the semiconductor wafer body for performing photoluminescence testing. The detection chip includes: Multiple periodically arranged quantum well intermixing regions and non-quantum well intermixing regions, wherein the particle doping in the quantum well intermixing regions is the same as the particle doping in the quantum well doping layer contained in the semiconductor wafer body; multiple quantum well intermixing regions receive laser beams to generate photoluminescence reactions, and interference occurs between the light emitted by the multiple quantum well intermixing regions, so that the signal intensity of the wavelength spectrum line emitted by the detection chip is enhanced.

2. The detection chip according to claim 1, wherein The quantum well intermixing regions are test lines, and the test lines and the non-quantum well intermixing regions are arranged alternately.

3. The detection chip according to claim 2, wherein, The quantum well intermixing regions are linearly arranged, and the distance between any adjacent quantum well intermixing regions is equal or unequal.

4. The detection chip according to claim 1, wherein The quantum well intermixing regions are test patterns, the non-quantum well intermixing regions are arranged around the test patterns, and multiple test patterns are arranged in a matrix.

5. The detection chip according to claim 4, wherein The test pattern includes at least one of a circle or a polygon.

6. The detection chip according to claim 1, wherein The total area of the multiple quantum well mixing regions is 0.5 mm 2 -1.5 mm 2 .

7. The detection chip according to claim 6, characterized in that, The ratio range of the total area of the multiple quantum well intermixing regions to the total area of the multiple non-quantum well intermixing regions is 5-10.

8. The detection chip according to claim 1, wherein, The distance between the surface of the quantum well intermixing region and the surface of the non-quantum well intermixing region is less than 2 μm.

9. The detection chip according to claim 1, wherein, The detection chip further includes at least one alignment mark for alignment.

10. A detection system for testing the detection chip according to any one of claims 1-9, characterized in that, Including: A semiconductor workbench; A laser light source for generating a laser beam, and the laser beam irradiates the detection chip carried on the semiconductor workbench to cause the detection chip to generate a photoluminescence reaction and emit light; A spectrometer that receives the light through an optical processing system, detects the light, and measures the wavelength spectrum of the detection chip; An imaging system connected to the spectrometer through a USB data cable, images the wavelength spectrum, and displays the blue shift condition of the wavelength spectrum to judge the anti-disaster optical damage characteristics of the semiconductor wafer.

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