Method for prolonging service life of InGaAs chip

Abstract

The invention relates to the technical field of the service life of an InGaAs chip, in particular to a method for prolonging the service life of the InGaAs chip, which comprises the following steps of: S1, selecting a product; S2, preprocessing in an oxygen-free drying oven: putting a chip into the oxygen-free drying oven, and putting the chip on a clean stainless steel iron frame in the oxygen-free drying oven; s3, setting a gradient temperature curve; S4, standing and observing: placing the chip in a nitrogen cabinet; s5, sorting products meeting the specification: sorting according to the reverse leakage current of the chip and other related performance indexes; according to the scheme, experiments and practical application verification are carried out on multiple batches of chips, the performance of the chips subjected to heat treatment in a high-temperature service life test HTOL is obviously superior to that of unprocessed chips, and the reverse leakage current of the chips can still be kept at a low level after long-time operation; and the risk of chip failure caused by the increase of the reverse leakage current is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of InGaAs chip lifespan, and in particular to a method for improving the lifespan of an InGaAs chip. Background Art

[0002] In today's era of rapid technological development, semiconductor chips are the core components of many electronic devices, and their performance and reliability directly affect the overall performance of the equipment. InGaAs chips, with their excellent characteristics in high electron mobility, high saturated electron velocity, and high sensitivity to specific wavelengths of light, have always been an important bottleneck restricting their further widespread application and performance improvement. During long-term use, chips will be affected by a variety of complex factors, causing their performance to gradually decline or even fail. Therefore, a method for improving the life of InGaAs chips is needed.

[0003] InGaAs chips face life problems caused by various factors during actual use. These problems seriously affect the performance stability and reliability of the chip, and restrict its wide application in various fields. High temperature environment is one of the main external factors affecting the life of the chip. Under high temperature, the thermal motion of atoms inside the chip intensifies, which will accelerate the aging and performance degradation of the material. High temperature will accelerate the chemical reaction rate inside the chip, causing the chemical bonds of the material to break or recombine, thereby affecting the electrical performance and structural stability of the chip. High temperature will also cause electromigration of the metal interconnect structure inside the chip, resulting in increased resistance of the metal wire or even open circuit, which will eventually cause the chip to fail.

[0004] Therefore, a method for improving the life of InGaAs chips is proposed. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings in the prior art and to propose a method for improving the life of an InGaAs chip.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A method for improving the life of an InGaAs chip, comprising S1, product selection: selecting a chip with good electrical properties, and accurately measuring various electrical parameters of the chip, such as resistance, capacitance, current, voltage characteristics, etc., through professional electrical testing equipment to ensure that these parameters are within a normal design range; the appearance of the selected chip should be normal, without any visible flaws, cracks, scratches or contamination on the surface; S2. Pretreatment in an oxygen-free oven: The chip is placed in an oxygen-free oven on a clean stainless steel rack in the oxygen-free oven; S3. Set the gradient temperature curve: adopt the gradient control mode, the heating process should be carried out slowly, and the temperature should be gradually increased at a certain rate, so that the materials inside the chip can gradually adapt to the temperature change and avoid excessive thermal stress caused by sudden temperature rise; after reaching the main temperature, keep the constant temperature for 1-2 hours to ensure that the materials inside the chip undergo sufficient physical and chemical changes, and realize the enhancement of the adhesion between the passivation layer and the substrate material and the optimization of the crystal structure; S4, static observation: place the chip in a nitrogen cabinet; S5. Sorting of products that meet the specifications: sorting according to the chip's reverse leakage current and other relevant performance indicators.

[0007] Preferably, in said S1, when selecting products, the chip is carefully observed under a microscope to ensure that the chip surface is flat and smooth without any abnormal traces. At the same time, it is necessary to ensure that the chip surface is free of pollution to avoid chemical reactions between pollutants and the chip during the heat treatment process, thereby affecting the final electrical results.

[0008] Preferably, before the pretreatment in the anaerobic oven in S2, the nitrogen valve of the anaerobic oven needs to be opened in advance so that the nitrogen can fully replace the air inside the oven to ensure that the oxygen concentration inside the oven is reduced to an extremely low level.

[0009] Preferably, in S3, when setting the gradient temperature curve, the cooling process also needs to be carried out slowly. During the entire temperature curve setting process, a high-precision temperature control board is needed to accurately control the temperature and monitor the temperature changes in real time to ensure that the temperature curve is consistent with the preset parameters. Through the precise control of the temperature control board, the heating rate, constant temperature time and cooling rate can be accurately adjusted.

[0010] Preferably, the nitrogen cabinet can provide a dry, low-oxygen environment. By standing in the nitrogen cabinet for 14-21 days, the materials inside the chip can fully recover to a stable state, and the reverse leakage current will gradually stabilize.

[0011] Preferably, in said S5, when sorting products that meet the specifications, the reverse leakage current of the chip after heat treatment generally cannot be restored to the value before heat treatment, but as long as it is still within the specification range, and in HTOL, the reverse leakage current of the pre-treated product deteriorates more slowly than that of normal products, then the chip is regarded as a qualified product, and the chips with reverse leakage current exceeding the specification range or performing poorly in other performance tests are eliminated.

[0012] The beneficial effects of the present invention are: This solution has been verified through experiments and actual applications on multiple batches of chips. The performance of the heat-treated chips in the high-temperature operating life experiment HTOL is significantly better than that of the untreated chips. The reverse leakage current of the chip can still be maintained at a low level after long-term operation, greatly reducing the risk of chip failure due to increased reverse leakage current. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic flow chart of a method for improving the life of an InGaAs chip proposed by the present invention; Figure 2 It is a reference diagram of temperature and time when setting the gradient temperature curve; Figure 3 It is a curve diagram of the aging test data of pre-treated product No. 1 at 2000 hours; Figure 4 It is a curve diagram of the aging test data of pre-treated product No. 4 at 2000 hours; Figure 5 This is a curve diagram of the aging test data of pre-treated product No. 9 at 2000 hours; Figure 6 This is a curve diagram of the aging test data of normal product No. 1 after 2000 hours; Figure 7 This is a curve diagram of the aging test data of normal product No. 9 after 2000 hours; Figure 8 This is a curve diagram of the normal product No. 13's 2000-hour aging test data. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0015] Example: Refer to Figure 1-8 , a method for improving the life of an InGaAs chip, comprising: S1. Product selection: Select chips with good electrical properties, which means that the circuit connection inside the chip is correct, the electronic transmission is smooth, and it can normally realize its predetermined electrical functions. Use professional electrical testing equipment to accurately measure the various electrical parameters of the chip, such as resistance, capacitance, current, voltage characteristics, etc., to ensure that these parameters are within the normal design range; the appearance of the selected chip should be normal, without any visible flaws, cracks, scratches or pollution on the surface. These appearance defects may affect the performance and reliability of the chip, and even cause damage to the chip due to stress concentration during the heat treatment process; S2. Pretreatment in an oxygen-free oven: The chips are placed in an oxygen-free oven on a clean stainless steel rack. Stainless steel has good high temperature resistance and chemical stability, is not likely to release harmful substances at high temperatures, and will not react chemically with the product. S3. Set the gradient temperature curve: adopt the gradient control mode, the heating process should be carried out slowly, and the temperature should be gradually increased at a certain rate, so that the materials inside the chip can gradually adapt to the temperature change and avoid excessive thermal stress caused by sudden temperature rise; after reaching the main temperature, keep the constant temperature for 1-2 hours to ensure that the materials inside the chip undergo sufficient physical and chemical changes, and realize the enhancement of the adhesion between the passivation layer and the substrate material and the optimization of the crystal structure; S4, static observation: place the chip in a nitrogen cabinet; S5. Sorting of products that meet the specifications: sorting according to the chip's reverse leakage current and other relevant performance indicators.

[0016] Specifically, S1. When selecting products, carefully observe the chip under a microscope to ensure that the chip surface is flat and smooth without any abnormal traces. At the same time, ensure that the chip surface is free of pollution to avoid chemical reactions between pollutants and chips during heat treatment, thereby affecting the final electrical results.

[0017] Furthermore, before S2 and pretreatment in the oxygen-free oven, the nitrogen valve of the oxygen-free oven needs to be opened in advance to allow the nitrogen to fully replace the air inside the oven and ensure that the oxygen concentration inside the oven is reduced to an extremely low level. Nitrogen, as an inert gas, has stable chemical properties and is not easy to react with chip materials, and can provide a safe protective atmosphere for the chip.

[0018] The oxygen-free oven pretreatment is a crucial link in the entire heat treatment process. Its main purpose is to create a low-oxygen environment for the chip, effectively preventing the chip's passivation layer or surface electrode from being damaged by oxidation during the heat treatment process. Under high temperature conditions, oxygen is highly active and can easily react chemically with metal elements and other sensitive materials in the chip, leading to problems such as degradation of the passivation layer and oxidation corrosion of the electrode, which seriously affects the chip's electrical performance and life.

[0019] S3. Setting a gradient temperature curve is a key step in the heat treatment process. Its purpose is to avoid excessive stress inside the chip due to excessive temperature changes, thereby affecting the performance and reliability of the chip. If the chip is directly raised to the main temperature of the heat treatment or directly lowered from the main temperature to room temperature, materials such as BCB or PBO will produce large deformation stress when they are thermoformed again due to rapid temperature changes. This excessive deformation stress will seriously affect the structure that connects the upper and lower areas as a passivation layer, resulting in abnormal contact, which in turn causes the chip's reverse leakage current to be high, and ultimately causes the chip to fail prematurely in the HTOL high-temperature working life experiment; like Figure 2 As shown, the heating and cooling processes also need to be carried out slowly. During the entire temperature curve setting process, a high-precision temperature control board is required to accurately control the temperature and monitor the temperature changes in real time to ensure that the temperature curve is consistent with the preset parameters. Through the precise control of the temperature control board, the heating rate, constant temperature time and cooling rate can be accurately adjusted, thereby ensuring that the chip is always in the best temperature environment during the heat treatment process, maximizing the performance and reliability of the chip.

[0020] The nitrogen cabinet can provide a dry, low-oxygen environment to further protect the chip from external environmental factors and ensure that the chip is not disturbed during the performance stabilization process. By standing in the nitrogen cabinet for 14-21 days, the materials inside the chip can fully recover to a stable state, and the reverse leakage current will gradually stabilize. S5. When sorting products that meet the specifications, the reverse leakage current of the chip after heat treatment generally cannot be restored to the value before heat treatment, but as long as it is still within the specification range, and in HTOL, the reverse leakage current of the pre-treated product deteriorates slower than that of normal products, then the chip is considered a qualified product. Chips with reverse leakage current exceeding the specification range or poor performance in other performance tests will be eliminated. Through a strict sorting process, chips with stable performance and high reliability can be screened out.

[0021] Test 1: like Figure 3 As shown, the pre-treated product No. 1 was tested, and the dark current increased to about 20nA as the aging time reached 168 hours, and the dark current increased to a maximum of about 120nA as the aging time reached 500 hours. After that, with the continuous aging, the dark current showed a significant downward trend, and finally dropped to about 10nA at 2080 hours. like Figure 4As shown, the pre-treated product No. 4 was experimented, and the dark current increased to about 20nA as the aging time reached 168 hours, and increased to a maximum value of about 100nA as the aging time reached 500 hours. Then, with continued aging, the dark current showed a clear downward trend, and finally dropped to about 10nA at 2080 hours.

[0022] like Figure 5 As shown, the pre-treated product No. 9 was experimented, and the dark current increased to about 10nA as the aging time reached 168 hours, and increased to a maximum value of about 70nA as the aging time reached 1300 hours. Then, with continued aging, the dark current showed a clear downward trend, and finally dropped to about 10nA at 2080 hours.

[0023] Conclusion: From 0 hours to 500 hours, the dark current of the product showed an upward trend, but from 500 hours to 1300 hours, the dark current of the product showed a downward trend, and at 2000 hours the dark current level dropped to 0-20nA. This dark current value belongs to the normal value during the period of operation, and will not cause the product to generate excessive heat during operation and affect product performance; Test 2: 1. If Figure 6 As shown, when normal product No. 1 was experimented, the dark current increased to about 150nA as the aging time reached 72 hours. When it reached 159 hours, the dark current dropped to about 100nA. Then, with continued aging, the dark current showed a clear upward trend, and finally reached a maximum value of about 250nA at 2000 hours.

[0024] 2. If Figure 7 As shown, when the normal product No. 9 was experimented, the dark current increased to about 200nA as the aging time reached 72 hours, and slightly decreased to about 100nA at 159 hours. After that, with continued aging, the dark current showed a clear upward trend, and finally reached a maximum value of about 250nA at 2000 hours.

[0025] 3. If Figure 8 As shown, when normal product No. 13 was experimented, the dark current increased to about 200nA as the aging time reached 72 hours, and slightly decreased to about 150nA at 159 hours. After that, with continued aging, the dark current showed a clear upward trend, and finally reached a maximum value of about 250nA at 2000 hours.

[0026] Conclusion: It can be seen intuitively that with the increase of time, the dark current of normal products has been on an upward trend, reaching 300nA, which is about 15 times that of pre-processed products, and there is a trend of increasing with the progress of time. In the circuit, the excessive dark current of the chip will accelerate the aging and performance degradation of the internal materials of the chip and shorten the service life; excessive dark current, as a kind of noise current, will affect the high-frequency performance of the chip and affect the detection and recognition accuracy of the signal; in the measurement of optical signals, excessive dark current will cause large errors in the test results. When testing weak optical signals, the dark current will produce an additional background value, which makes the measured light intensity higher than the actual value, affecting the test's judgment of the true intensity of the optical signal.

[0027] Summary: The heat treatment improvement method proposed in this study has shown significant effectiveness in improving the life of InGaAs chips. Through experiments and practical application verification on multiple batches of chips, the results show that the performance of the heat-treated chips in the high-temperature working life experiment HTOL is significantly better than that of the untreated chips. The reverse leakage current of the chip can still be maintained at a low level after long-term operation, greatly reducing the risk of chip failure due to increased reverse leakage current.

[0028] However, this method also has certain limitations. This method is mainly used for InGaAs chips that use BCB and PBO as passivation layers and dielectric materials. The applicability of this method to chips using other materials needs further research and verification. Although heat treatment can improve the performance of the chip to a certain extent, it cannot completely eliminate the inherent defects inside the chip and the impact of external environmental factors on the chip life.

[0029] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0030] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. The machinery, parts and equipment all adopt conventional models in the prior art, and the circuit connection adopts the conventional connection method in the prior art, which will not be described in detail here.

[0031] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for improving the life of an InGaAs chip, characterized in that: include: S1. Product selection: Select chips with good electrical properties, and use professional electrical testing equipment to accurately measure the various electrical parameters of the chip, such as resistance, capacitance, current, voltage characteristics, etc., to ensure that these parameters are within the normal design range; the appearance of the selected chip should be normal, without any visible defects, cracks, scratches or pollution on the surface; S2. Pretreatment in an oxygen-free oven: The chip is placed in an oxygen-free oven on a clean stainless steel rack in the oxygen-free oven; S3. Set the gradient temperature curve: adopt the gradient control mode, the heating process should be carried out slowly, and the temperature should be gradually increased at a certain rate, so that the materials inside the chip can gradually adapt to the temperature change and avoid excessive thermal stress caused by sudden temperature rise; after reaching the main temperature, keep the constant temperature for 1-2 hours to ensure that the materials inside the chip undergo sufficient physical and chemical changes, and realize the enhancement of the adhesion between the passivation layer and the substrate material and the optimization of the crystal structure; S4, static observation: place the chip in a nitrogen cabinet; S5. Sorting of products that meet the specifications: sorting according to the chip's reverse leakage current and other relevant performance indicators.

2. A method for improving the life of an InGaAs chip according to claim 1, characterized in that: S1. When selecting products, carefully observe the chip under a microscope to ensure that the chip surface is flat and smooth without any abnormal marks. At the same time, ensure that the chip surface is free of pollution.

3. A method for improving the life of an InGaAs chip according to claim 1, characterized in that: Before the pretreatment in the oxygen-free oven in S2, the nitrogen valve of the oxygen-free oven needs to be opened in advance to allow the nitrogen to fully replace the air inside the oven, ensuring that the oxygen concentration inside the oven is reduced to an extremely low level.

4. A method for improving the life of an InGaAs chip according to claim 1, characterized in that: In S3, when setting the gradient temperature curve, the cooling process also needs to be carried out slowly. During the entire temperature curve setting process, a high-precision temperature control board is needed to accurately control the temperature and monitor the temperature changes in real time to ensure that the temperature curve is consistent with the preset parameters. Through the precise control of the temperature control board, the heating rate, constant temperature time and cooling rate can be accurately adjusted.

5. A method for improving the life of an InGaAs chip according to claim 1, characterized in that: The nitrogen cabinet can provide a dry, low-oxygen environment. By standing in the nitrogen cabinet for 14-21 days, the materials inside the chip can fully recover to a stable state, and the reverse leakage current will gradually stabilize.

6. A method for improving the life of an InGaAs chip according to claim 1, characterized in that: In S5, when sorting products that meet the specifications, the reverse leakage current of the chip after heat treatment generally cannot be restored to the value before heat treatment, but as long as it is still within the specification range, and in HTOL, the reverse leakage current of the pre-treated product deteriorates more slowly than that of normal products, the chip is considered a qualified product. Chips with reverse leakage current exceeding the specification range or performing poorly in other performance tests are eliminated.

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