A method and system for improving chip test temperature control accuracy

Abstract

The present application provides a method and system for improving the temperature control accuracy of chip testing, which relates to the field of chip testing temperature control. The method includes: obtaining the temperature value of a specific position of the chip through an infrared temperature sensor; obtaining infrared imaging of different positions of the chip through a thermal imager; determining the temperature prediction value of different positions of the chip based on the temperature value of the specific position and the infrared imaging; if it is detected that the maximum and minimum values ​​in the temperature prediction value are both within a preset temperature range, then calculating the difference between the maximum and minimum values; if it is detected that the difference exceeds a preset change threshold, then adjusting the power output of the heating or cooling system so that the difference does not exceed the preset change threshold. The implementation of this method can monitor the uniformity of the chip temperature distribution, and timely compensate when the temperature of certain parts of the chip changes too much relative to other parts, so as to avoid local overheating or overcooling affecting chip performance, thereby improving the temperature control accuracy of chip testing.

Description

Technical Field

[0001] The present application relates to the field of chip test temperature control, and in particular to a method and system for improving chip test temperature control accuracy. Background Art

[0002] In the current semiconductor industry, temperature control during chip testing is a key factor in ensuring product quality and performance. Since chips generate heat during operation, uneven temperature distribution may cause circuit malfunction or performance degradation. Therefore, achieving precise temperature control and ensuring that the temperature of each part of the chip is balanced is an important requirement for improving test accuracy and reliability.

[0003] In the related art, a temperature sensor is usually used to measure the temperature at a specific location in the chip or test equipment, and this is used as a control system to adjust the heating or cooling equipment to achieve temperature control. This method can monitor the thermal state of the chip in real time and adjust the temperature in time when the chip temperature exceeds the preset temperature range.

[0004] However, during the process of adjusting the temperature of the chip, the chip may be heated or cooled unevenly, resulting in uneven temperatures in different parts of the chip and unstable chip performance. Summary of the invention

[0005] The present application provides a method and system for improving the temperature control accuracy of chip testing, which is used to identify and adjust the performance instability problem of the chip caused by overheating or overcooling of a small area.

[0006] In a first aspect, the present application provides a method for improving the temperature control accuracy of chip testing, which is applied to a temperature control system. The method comprises: Obtain the temperature value of a specific position of the chip through an infrared temperature sensor; Acquire infrared images of different positions of the chip by a thermal imager, wherein the infrared images of the different positions include infrared images corresponding to the specific position; Determine predicted temperature values ​​at different positions of the chip based on the temperature value at the specific position and the infrared imaging; If it is detected that the maximum value and the minimum value in the temperature prediction value are both within the preset temperature range, the difference between the maximum value and the minimum value is calculated; If it is detected that the difference exceeds a preset change threshold, the power output of the heating or cooling system is adjusted so that the difference does not exceed the preset change threshold.

[0007] Through the above embodiments, the temperature control system determines the predicted temperature values ​​of various locations on the chip based on the temperature values ​​of specific locations on the chip and the infrared imaging data of different locations. If the predicted maximum and minimum temperatures are both within the preset range but the difference between the two exceeds the preset threshold, the power output of the heating or cooling system is adjusted so that the temperature difference does not exceed the threshold. This method can monitor the uniformity of the chip temperature distribution, and when the temperature of certain parts of the chip changes too much relative to other parts, timely compensation is made to avoid local overheating or overcooling affecting chip performance, thereby improving the temperature control accuracy of chip testing.

[0008] In some embodiments, the step of determining the predicted temperature values ​​of different positions of the chip based on the temperature value of the specific position and the infrared imaging specifically includes: Obtaining information about the constituent materials of the chip at different locations; Determining the emissivity of the chip at different positions according to a preset emissivity table and the component material information, wherein the emissivity table records the emissivity corresponding to different materials; Based on the temperature value and infrared imaging at the specific location, the predicted temperature values ​​at other locations are calculated according to the emissivity.

[0009] Through the above embodiment, the temperature control system obtains the composition material information of different positions of the chip, and then determines the emissivity of different positions of the chip, and then calculates the temperature prediction value at different positions in combination with the infrared image difference of different positions. This method takes into account the differences in radiation characteristics of different materials and positions of the chip, and combines the measured reference point data to more accurately infer the temperature distribution of the entire chip, providing a basis for accurate temperature compensation control.

[0010] In some embodiments, the step of calculating the predicted temperature value at other locations based on the emissivity based on the temperature value at the specific location and the infrared imaging specifically includes: Calculating the radiation energy at the specific location based on the emissivity and temperature value at the specific location; Acquire the radiation energy of the chip at different positions; The temperature prediction values ​​at other locations are calculated based on the radiation energy and corresponding emissivity at different locations.

[0011] Through the above embodiments, the temperature control system obtains the radiation energy at different positions of the chip through the thermal imager, and then calculates the temperature prediction values ​​at different positions of the chip based on the radiation energy prediction values, providing a basis for subsequent precise temperature compensation control.

[0012] In some embodiments, after the step of determining the temperature prediction values ​​of different positions of the chip according to the temperature value of the specific position and the infrared imaging, the method further includes: If it is detected that the maximum value or the minimum value of the temperature prediction value exceeds the preset temperature range, the power output of the heating or cooling system is adjusted so that the maximum value or the minimum value does not exceed the preset temperature range.

[0013] Through the above embodiment, after the temperature control system detects that the extreme value of the temperature prediction value exceeds the preset temperature range, it directly adjusts the power to make the extreme value fall back to the allowable range. This method can quickly respond to abnormal fluctuations in chip temperature, avoid local excessively high or low temperatures that last for a long time and affect chip performance, and enable the temperature control system to ensure the stability of chip testing under a wide range of working conditions.

[0014] In some embodiments, after the step of calculating the difference between the maximum value and the minimum value if it is detected that both the maximum value and the minimum value in the temperature prediction value are within the preset temperature range, the method further includes: If it is detected that the difference does not exceed the preset change threshold, the average of the temperature prediction values ​​is determined as the current temperature value of the chip; and a temperature change curve is generated according to the current temperature value within the first preset time; Predicting the temperature change trend of the chip within a second preset time in the future according to the temperature change curve; According to the temperature change trend, the heating or cooling system is controlled to perform temperature compensation in advance.

[0015] Through the above embodiments, when the extreme value and variation range of the temperature prediction value meet the requirements, the temperature control system further generates a temperature change curve based on the average of multiple consecutive temperature predictions, predicts the change trend of the chip temperature in the future, and performs compensation control in advance. This method analyzes the dynamic change law of the chip temperature, takes measures in advance to suppress the temperature from deviating from the target value, and reduces the temperature fluctuation caused by control lag.

[0016] In some embodiments, before the step of acquiring the temperature value of a specific position of the chip by using an infrared temperature sensor, the method further includes: The humidity of the surrounding air and the air velocity are detected by a humidity sensor and an air velocity sensor respectively; If it is detected that the air humidity exceeds the corresponding preset humidity threshold, the voltage level of the heating plate is adjusted to reduce the air humidity to below the preset humidity threshold; If it is detected that the air flow rate exceeds the corresponding preset flow rate threshold, the coolant circulation rate is adjusted to reduce the air flow rate to below the preset flow rate threshold.

[0017] Through the above embodiments, the temperature control system introduces the detection and adjustment of environmental humidity and airflow to prevent the fluctuation of environmental factors from affecting the accuracy of chip temperature measurement and control. By adding dehumidification and airflow suppression measures in the heating and cooling system, the interference of environmental factors can be reduced, creating more stable and controllable test conditions for the chip.

[0018] In some embodiments, after the step of acquiring infrared images of different positions of the chip by a thermal imager, the method further includes: After each preset interval period, respectively obtain the self-test data of the infrared temperature sensor and the thermal imager; If an abnormality is detected in the self-test data, an early warning message will be issued.

[0019] Through the above embodiments, the temperature control system adds a regular self-check function for the infrared temperature sensor and the thermal imager. By periodically monitoring the working status of the sensor and issuing a timely warning once an abnormality is found, temperature runaway due to accumulation of temperature measurement errors can be avoided, thereby improving the reliability of the long-term operation of the system.

[0020] In a second aspect, the present application provides a temperature control system, the temperature control system comprising: one or more processors and a memory; The memory is coupled to the one or more processors, and the memory is used to store computer program code, which includes computer instructions. The one or more processors call the computer instructions so that the temperature control system can implement a method for improving the temperature control accuracy of chip testing provided in the above embodiment, which will not be repeated here.

[0021] In a third aspect, the present application provides a computer-readable storage medium, including instructions. When the instructions are executed on a temperature control system, the temperature control system can implement a method for improving the temperature control accuracy of chip testing provided in the above embodiment, which will not be repeated here.

[0022] In a fourth aspect, the present application provides a computer program product. When the computer program product runs on a temperature control system, the temperature control system can implement a method for improving the temperature control accuracy of chip testing provided in the above embodiment, which will not be repeated here.

[0023] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: 1. Infrared temperature sensors and thermal imagers are integrated to measure and image the temperature of the chip at multiple points, and a spatial prediction model of the chip temperature is established in combination with the chip material characteristic data. This method can not only obtain the precise temperature value of the chip locally, but also comprehensively evaluate the uniformity of the temperature distribution of the chip as a whole, laying a measurement foundation for achieving precise temperature compensation control.

[0024] 2. By continuously recording the chip temperature changes and drawing the temperature curve, the chip temperature change trend in the future period is predicted, and the heating or cooling system is adjusted in advance accordingly, so that the temperature control system can actively respond to changes in the chip working state, reduce temperature fluctuations caused by control lag, and improve the stability of the chip testing process.

[0025] 3. The monitoring and adjustment mechanism of ambient humidity and air flow speed is integrated into the temperature control system. By integrating dehumidification and air flow suppression devices, the interference of environmental factors on chip temperature control is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of a method for improving the temperature control accuracy of chip testing in an embodiment of the present application; Figure 2 It is another flow chart of a method for improving the temperature control accuracy of chip testing in an embodiment of the present application; Figure 3 It is a schematic diagram of the structure of a physical device of the temperature control system in the embodiment of the present application. DETAILED DESCRIPTION

[0027] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to be used as limitations to the present application. As used in the specification and appended claims of the present application, the singular expressions "one", "a kind of", "said", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear indication to the contrary in the context. It should also be understood that the term "and / or" used in the present application refers to any or all possible combinations comprising one or more listed items.

[0028] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0029] For ease of understanding, the following is a flow chart of the method provided by this embodiment. Figure 1 As shown, it is a flow chart of a method for improving the temperature control accuracy of chip testing in an embodiment of the present application.

[0030] S101. Obtain the temperature value of a specific position of the chip through an infrared temperature sensor.

[0031] Specifically, the temperature control system arranges several infrared temperature sensors in the test device, points their probes at specific locations on the chip surface, such as the center area of ​​the chip, the boundary of the functional module and other temperature-sensitive points, and collects the infrared radiation intensity of these locations in real time. According to Planck's blackbody radiation law, there is a definite functional relationship between the radiation intensity and the surface temperature of the object. The temperature control system can convert the infrared radiation intensity signal into a real-time temperature reading at the corresponding location as input data for subsequent temperature analysis and control.

[0032] Among them, the infrared temperature sensor is a non-contact temperature measurement device that can use the infrared radiation emitted from the surface of an object to infer the temperature of the object without directly contacting the object being measured.

[0033] S102, obtaining infrared images of different positions of the chip through a thermal imager.

[0034] The temperature control system installs a high-pixel-resolution array thermal imager in the test device, points its infrared lens at the chip to be tested, and adjusts the focal length and field of view so that it can completely cover the chip surface. The uncooled infrared focal plane detector array in the thermal imager can sense infrared radiation of different intensities emitted from various positions on the chip and convert it into temperature signals at the corresponding positions. The built-in image processing unit of the thermal imager can automatically calculate the temperature value represented by each pixel and generate a pseudo-color-coded thermal image, namely infrared imaging. In infrared imaging, different colors correspond to different temperature ranges, which intuitively reflects the temperature distribution of various parts of the chip surface.

[0035] It should be noted that the infrared images obtained by the above thermal imager are obtained under the condition of the same reflectivity, but considering that the constituent materials of different positions of the chip may be different, the temperature value calculated by the thermal imager is not the actual temperature value of the corresponding position of the chip. Therefore, the infrared images generated by the thermal imager reflect the distribution of radiation energy at different positions on the chip surface.

[0036] S103, determining predicted temperature values ​​at different positions of the chip based on the temperature value at the specific position and infrared imaging.

[0037] The infrared imaging of different positions of the chip reflects the radiation energy of the corresponding position. The temperature control system determines that there is a certain functional relationship between the radiation intensity and the surface temperature of the object based on the Stefan-Boltzmann law, that is, the total radiation power of a black body (an idealized object that can completely absorb all incident radiation, neither reflect nor transmit) is proportional to the fourth power of its absolute temperature. Then, the surface temperature (temperature prediction value) of the object at the corresponding position is calculated based on the radiation energy of different positions of the chip.

[0038] S104: If it is detected that the maximum value and the minimum value in the temperature prediction value are both within the preset temperature range, the difference between the maximum value and the minimum value is calculated.

[0039] After obtaining the temperature prediction values ​​of different positions of the chip in step S103, the temperature control system selects the maximum and minimum values ​​in the temperature prediction values, and respectively determines whether the maximum and minimum values ​​are within the preset temperature range (e.g., industrial-grade chips usually require an ambient temperature of -40°C to 85°C, and the temperature range of military-grade chips can be extended to -55°C to 125°C.). If the maximum and minimum values ​​are both within the preset temperature range, the difference between the maximum and minimum values ​​is calculated. By comparing the difference with the preset change threshold, the temperature difference in different areas of the chip is evaluated.

[0040] S105: If it is detected that the difference exceeds a preset change threshold, the power output of the heating or cooling system is adjusted so that the difference does not exceed the preset change threshold.

[0041] When the temperature control system detects that the difference between the maximum and minimum values ​​in the temperature prediction value exceeds the preset change threshold, the temperature control system automatically starts the temperature compensation mechanism. Specifically, the temperature control system dynamically balances the temperature distribution inside the chip by adjusting the power output of the heater or refrigerator. For example, when it is detected that the difference ΔT between the highest and lowest temperatures of the chip exceeds 30°C (the preset change threshold), the temperature control system determines the main reason for the large temperature difference ΔT based on infrared imaging: whether it is due to excessively high temperature in the local area (the local color of the infrared imaging is darker, and the color of other areas is lighter), or uneven overall temperature distribution (uneven distribution of the color depth of the infrared imaging). If the temperature in an individual area is obviously too high, the power of the cooling fan above the area can be increased to strengthen the local heat extraction; at the same time, the heating power of other areas can be appropriately reduced to avoid aggravating the temperature imbalance. If the overall temperature distribution gradient of the chip is large, the power ratio of each heating unit can be optimized to match the power consumption distribution inside the chip while keeping the total heating power unchanged.

[0042] Specifically, the temperature control system establishes a mathematical model that reflects the temperature response of the chip based on the mechanism of heat conduction and heat radiation, and then combines the PID control algorithm to realize closed-loop feedback regulation of heating and cooling power. That is, when the ΔT value exceeds the upper threshold, the temperature control system automatically increases the cooling power and reduces the heating power; when the ΔT value is lower than the lower threshold, the cooling power is reduced and the heating power is increased accordingly. Through this dynamic balance method, the temperature distribution inside the chip can gradually become uniform and stable, and the ΔT value can be stably controlled within the threshold range.

[0043] In the above embodiment, the temperature control system determines the predicted temperature values ​​of various locations on the chip based on the temperature values ​​of specific locations on the chip and the infrared imaging data of different locations. If the predicted maximum and minimum temperatures are both within the preset range but the difference between the two exceeds the preset threshold, the power output of the heating or cooling system is adjusted so that the temperature difference does not exceed the threshold. This method can monitor the uniformity of the chip temperature distribution, and when the temperature of certain parts of the chip changes too much relative to other parts, timely compensation is made to avoid local overheating or overcooling affecting chip performance, thereby improving the temperature control accuracy of chip testing.

[0044] The following is a more detailed description of the process of the method provided by this embodiment. Figure 2 As shown, it is another flow chart of a method for improving the temperature control accuracy of chip testing in an embodiment of the present application.

[0045] S201. Detect the ambient air humidity and air flow rate through a humidity sensor and an air flow rate sensor respectively.

[0046] Specifically, digital temperature and humidity sensors and thermal wind speed sensors can be arranged in the test device and connected to the controller of the temperature control system through the RS485 bus or wireless communication module. The controller queries the output signals of each sensor at a certain frequency to obtain the humidity percentage and air flow rate value of the current environment.

[0047] S202: Whether the air humidity exceeds a preset humidity threshold.

[0048] After receiving the data from the humidity sensor, the temperature control system compares it with the preset humidity threshold. When the air humidity exceeds the preset threshold, the system proceeds to step S206, where the temperature control system sends a start instruction to the dehumidification device to reduce the water content of the air by heating or adsorption. On the contrary, if the air humidity is detected to be below the preset threshold, the system proceeds to step S203 to determine the relationship between the air flow rate and the preset flow rate threshold.

[0049] Among them, the preset humidity threshold is usually determined based on comprehensive consideration of factors such as the hygroscopic characteristics of the chip material and the surface treatment process. For example, for bare silicon wafers, it is more appropriate to control the relative humidity below 40%; while for plastic-sealed chips, the humidity can be relaxed to around 60%, which is not limited here.

[0050] S203: Whether the air flow rate exceeds a preset flow rate threshold.

[0051] After reading the data from the air velocity sensor, the temperature control system compares it with the preset velocity threshold. When the air velocity exceeds the preset velocity threshold, the system proceeds to step S207, where the temperature control system issues a speed reduction instruction to reduce the velocity below the threshold by adjusting the fan speed or air flow diversion. On the contrary, if the air velocity does not exceed the preset velocity threshold, the system proceeds to steps S204 and S205, where the detection data of the infrared temperature sensor and the thermal imager are normally obtained.

[0052] In the above embodiment, the temperature control system introduces the detection and adjustment of environmental humidity and airflow to prevent the fluctuation of environmental factors from affecting the accuracy of chip temperature measurement and control. By adding dehumidification and airflow suppression measures in the heating and cooling system, the interference of environmental factors can be reduced, creating more stable and controllable test conditions for the chip.

[0053] S204, obtaining self-test data of the infrared temperature sensor and the thermal imager respectively after each preset interval period.

[0054] Specifically, when the temperature control system detects that the accumulated working time reaches a preset interval period (such as 240 hours), it starts the sensor self-test program during the interval of the test task. Through the built-in standard black body furnace or calibration radiation source of the sensor, the sensor collects a set of standard temperature or radiation intensity data respectively, and compares them with the theoretical value to calculate the error size. If an abnormality is detected in the self-test data, that is, the error exceeds the preset error threshold, an early warning message is issued. The sending method of the early warning message includes but is not limited to SMS, voice, etc., which are not limited here.

[0055] In the above embodiment, the temperature control system adds a regular self-inspection function for the infrared temperature sensor and the thermal imager. By periodically monitoring the working status of the sensor and issuing a timely warning once an abnormality is found, temperature runaway due to accumulation of temperature measurement errors can be avoided, thereby improving the long-term operation reliability of the system.

[0056] S205 , obtaining the temperature value of a specific position of the chip and infrared imaging of different positions.

[0057] The specific implementation process of this step has been introduced in step S101 and step S102 and will not be repeated here.

[0058] S206: Adjust the voltage level of the heating plate to reduce the air humidity to below a preset humidity threshold.

[0059] When it is detected that the air humidity exceeds the standard, the temperature control system automatically starts the dehumidification program. Optionally, by increasing the surface temperature of the heating plate, the surrounding air expands due to heat and the relative humidity decreases. Specifically, according to the degree of humidity exceeding the standard, the temperature control system adjusts the duty cycle of the PWM signal according to the PID algorithm and outputs different voltages to the heating plate to appropriately increase its temperature and reduce humidity.

[0060] S207, adjusting the coolant circulation rate to reduce the air flow rate to below a preset flow rate threshold.

[0061] Specifically, the temperature control system can connect a set of liquid cooling circuits in parallel with the air cooling system, and the refrigeration compressor drives the coolant to circulate in the pipeline. When the coolant flows through the radiator of the fan, it takes away some heat, causing the supply air temperature to drop. By changing the power of the compressor, the flow rate of the coolant can be adjusted, thereby affecting the heat dissipation efficiency and speed of the fan. The temperature control system uses the PID algorithm to control the power output of the compressor based on the data from the air flow velocity sensor, and ultimately maintains the air flow velocity below the preset threshold.

[0062] S208. Obtaining component material information of the chip at different positions.

[0063] Based on the chip material structure diagram and process flow documents uploaded by relevant technicians, the temperature control system obtains the material category distribution of different functional areas and layers of the chip, such as the substrate may be silicon material, the metal interconnect layer may be copper or aluminum, and the insulating layer may be silicon dioxide. Combining this material information with the chip layout diagram, the temperature control system can build a complete material distribution database, laying the foundation for subsequent emissivity calculation and temperature inference.

[0064] S209, determining the emissivity of the chip at different positions according to a preset emissivity table and component material information.

[0065] After obtaining the material distribution information of each position of the chip, the temperature control system needs to further determine the radiation emissivity of these positions. Specifically, the temperature control system has a pre-stored emissivity comparison table of common materials, which records the typical emissivity values ​​of various materials at different temperatures and surface conditions. By querying the material distribution database to obtain the material type at each position of the chip, and then finding the emissivity reference value corresponding to the material from the comparison table, the theoretical emissivity distribution diagram of each position of the chip can be obtained. In actual application, the emissivity value can also be corrected through calibration tests to compensate for the influence of factors such as material surface roughness and degree of oxidation.

[0066] S210, obtaining radiation energy of the chip at different positions.

[0067] When the chip is powered on, the temperature inside is uneven and presents a certain spatial distribution. The temperature control system can detect the radiation energy of the chip at different positions through a thermal imager. Among them, the thermal imager is equipped with an infrared detector that can sense the infrared radiation energy emitted by an object. The thermal imager scans the surface of the chip through an optical system and collects infrared radiation from different positions of the chip. These radiations are received by the sensors on the detector, and each sensor corresponds to a tiny area on the chip. The detector converts the received infrared radiation energy into electrical signals. The strength of the electrical signal generated by each sensor is proportional to the infrared radiation energy it receives. These electrical signals are converted into digital data, and the thermal distribution image of the chip surface is reconstructed through algorithms. Each pixel represents the radiation energy and temperature of a specific position on the chip.

[0068] S211. Calculate the temperature prediction values ​​at other locations based on the radiation energy and corresponding emissivity at different locations.

[0069] The calculation formula for the predicted temperature value is: Among them, T i is the temperature prediction value of the i-th pixel position in the infrared image corresponding to the chip, P i is the radiation energy of the i-th pixel position in the infrared image corresponding to the chip, ε i is the material reflectivity of the i-th pixel position in the infrared image corresponding to the chip, and σ is the Stefan-Boltzmann constant (approximately 5.67×10 -8 Watt / square meter·fourth power of Kelvin).

[0070] Substituting the radiation energy and the corresponding emissivity at different positions into the above formula, the temperature prediction values ​​at other positions except the specific position can be calculated. For the temperature value prediction at a specific position, the emissivity of the specific position point can be directly set in the thermal imager, and the temperature prediction value corresponding to the specific position point can be directly calculated based on the radiation energy obtained at the specific position point and the calculation formula of the above temperature prediction value.

[0071] Furthermore, all temperature prediction values ​​are combined to obtain a temperature prediction distribution map of the chip.

[0072] In the above embodiment, the temperature control system obtains the composition material information of different positions of the chip, and then determines the emissivity of different positions of the chip, and then calculates the temperature prediction value at different positions in combination with the infrared image difference of different positions. This method takes into account the differences in radiation characteristics of different materials and positions of the chip, and combines the measured reference point data to more accurately infer the temperature distribution of the entire chip, providing a basis for accurate temperature compensation control.

[0073] S212: Whether the maximum value or the minimum value exceeds the preset temperature range.

[0074] The temperature control system scans the predicted temperature distribution map of the chip point by point to find the maximum and minimum values, and then compares the maximum and minimum values ​​with the upper and lower temperature limits of the chip respectively. If the maximum value exceeds the upper limit or the minimum value is lower than the lower limit, it is determined that the temperature distribution of the chip has exceeded the safe range, and immediate measures need to be taken to bring the temperature back to the allowable range, that is, enter step S214. On the contrary, if the maximum value does not exceed the upper limit and the minimum value is greater than the lower limit, it is determined that the overall temperature distribution of the chip is still within the controllable range, and the next step of evaluating the temperature uniformity can be entered, that is, entering step S213.

[0075] In the above embodiment, after the temperature control system detects that the extreme value of the temperature prediction value exceeds the preset temperature range, it directly adjusts the power to make the extreme value fall back to the allowable range. This method can quickly respond to abnormal fluctuations in chip temperature, avoid local excessively high or low temperatures that last for a long time and affect chip performance, and enable the temperature control system to ensure the stability of chip testing under a wide range of working conditions.

[0076] S213: Whether the difference exceeds a preset change threshold.

[0077] Specifically, the temperature control system calculates the difference between the maximum and minimum values ​​in the temperature prediction distribution diagram obtained in step S211 to obtain the maximum temperature difference of the current chip. The maximum temperature difference is compared with the preset temperature difference threshold. If the maximum temperature difference exceeds the preset temperature difference threshold, it is determined that the temperature distribution inside the chip is not uniform enough, the local temperature difference is too large, and measures need to be taken to reduce the temperature difference, that is, enter step S215. If the maximum temperature difference does not exceed the preset temperature difference threshold, it is determined that the temperature gradient of the current chip is within an acceptable range, and the current temperature control strategy can be maintained, thereby executing subsequent steps such as S216.

[0078] S214, adjusting the power output of the heating or cooling system so that the maximum or minimum value does not exceed a preset temperature range.

[0079] If the maximum temperature of the chip exceeds the upper temperature limit, it is determined that there is a risk of overheating in the local area and heat removal needs to be strengthened. The temperature control system first increases the power of the air cooling or liquid cooling equipment, such as increasing the speed of the fan, increasing the flow of the coolant, etc., to promote the convection dissipation of heat on the chip surface. Specifically, through feedback control algorithms such as PID, the output power of the cooling and heating device is automatically adjusted according to the difference between the maximum temperature and the upper temperature limit until the maximum temperature is maintained at the target value below the upper temperature limit.

[0080] If the lowest temperature of the chip is lower than the lower limit temperature, it is determined that there is a risk of local freezing or failure of the chip, and the temperature of the chip needs to be appropriately increased. The temperature control system will reduce the operating power of the refrigeration equipment accordingly to weaken the effect of convection heat dissipation. At the same time, the power supply of the heating element will be increased to increase the heating amount of the chip. Through closed-loop control, the lowest temperature is stabilized at a safe level higher than the lower limit temperature.

[0081] S215, adjusting the power output of the heating or cooling system so that the difference does not exceed a preset change threshold.

[0082] When it is detected that the maximum temperature difference in the chip exceeds the preset change threshold, the temperature control system comprehensively considers the spatial distribution characteristics of the chip's thermal field and implements differentiated temperature control measures for different areas in a targeted manner. Specifically, for areas with relatively high temperatures, the temperature control system can control to increase the active heat dissipation intensity of the area, such as increasing the fan speed, increasing the coolant flow rate, etc.; while for areas with relatively low temperatures, the power of its auxiliary heating device can be increased, such as increasing the heating power of the local area of ​​the heating plate. By independently adjusting the temperature control parameters of each area, the temperature rise or cooling rates of different parts of the chip can be made consistent, thereby homogenizing the internal temperature distribution, so that the maximum temperature difference in the chip can always be controlled within the preset change threshold.

[0083] S216: Determine the average of the temperature prediction values ​​as the current temperature value of the chip.

[0084] The temperature control system calculates the arithmetic mean value based on the temperature prediction values ​​of each area of ​​the chip and uses the mean value as the current temperature value of the entire chip.

[0085] S217, generating a temperature change curve according to the current temperature value within the first preset time, and predicting the temperature change trend of the chip within the future second preset time.

[0086] The temperature control system continuously records multiple current temperature values ​​within a certain time range, and plots a temperature change curve with time as the horizontal axis and temperature as the vertical axis. Based on the temperature change pattern over a period of time, it is possible to intuitively determine whether the chip temperature is rising, falling or stable, providing an intuitive basis for predicting future temperature trends.

[0087] Furthermore, the temperature control system can use data extrapolation and other methods to predict the trend of chip temperature changes in the future. Optional temperature prediction methods include linear extrapolation, polynomial fitting, time series analysis, etc. Through these methods, qualitative or quantitative estimates of the general trend of future temperature can be made based on the temperature change law in the past period of time. For example, based on the 10-minute temperature change curve obtained previously, a linear function T=0.5t+75 is obtained by least squares fitting, where T is temperature and t is time, in minutes. This function shows that the current chip temperature is rising at a rate of approximately 0.5°C per minute. If t=20 is substituted into the function, it can be predicted that the chip temperature will rise to T=0.5×20+75=85°C after 10 minutes (t=10+20=20). Based on this, the temperature control system starts cooling in advance to prevent the temperature from being too high and affecting the chip performance.

[0088] S218. Control the heating or cooling system to perform temperature compensation in advance according to the change trend.

[0089] After predicting the future temperature change trend of the chip, the temperature control system needs to control the heating or cooling equipment in advance to keep the temperature within the target range as much as possible. Specifically, if the prediction results show that the chip temperature may be too high, the power of the refrigeration equipment will be started or increased; if the predicted temperature may be too low, the power of the heating equipment will be started or increased. By adjusting in advance, the temperature can be controlled within a reasonable range before it actually deviates, avoiding large fluctuations. At the same time, due to early intervention, the temperature control equipment can change the power slowly and steadily, reducing interference with the chip operation.

[0090] The temperature control system of the embodiment of the present invention is an electronic device. Figure 3 A schematic diagram of the architecture of an electronic device suitable for implementing an embodiment of the present invention is shown.

[0091] It should be noted that Figure 3 The electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0092] Those skilled in the art will appreciate that all or part of the steps in the various methods of the above embodiments can be completed by instructions (computer programs), or by controlling related hardware through instructions (computer programs), and the instructions can be stored in a computer-readable storage medium and loaded and executed by a processor. The electronic device of this embodiment includes a storage medium and a processor, wherein a plurality of instructions are stored in the storage medium, and the instructions can be loaded by the processor to execute any step of the method provided in the embodiment of the present invention.

[0093] Specifically, the storage medium and the processor are electrically connected directly or indirectly to realize data transmission or interaction. For example, these elements can be electrically connected to each other through one or more signal lines. The storage medium stores computer execution instructions for implementing the data access control method, including at least one software function module that can be stored in the storage medium in the form of software or firmware. The processor executes various functional applications and data processing by running the software program and module stored in the storage medium. The storage medium can be, but is not limited to, random access storage medium (Random Access Memory, referred to as: RAM), read-only storage medium (Read Only Memory, referred to as: ROM), programmable read-only storage medium (Programmable Read-Only Memory, referred to as: PROM), erasable read-only storage medium (Erasable Programmable Read-Only Memory, referred to as: EPROM), electrically erasable read-only storage medium (Electric Erasable Programmable Read-Only Memory, referred to as: EEPROM), etc. Among them, the storage medium is used to store programs, and the processor executes the program after receiving the execution instruction.

[0094] Furthermore, the software programs and modules in the above-mentioned storage medium may also include an operating system, which may include various software components and / or drivers for managing system tasks (such as memory management, storage device control, power management, etc.), and may communicate with various hardware or software components to provide an operating environment for other software components. The processor may be an integrated circuit chip having signal processing capabilities. The above-mentioned processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc., which may implement or execute the various methods, steps, and logic flow diagrams disclosed in this embodiment. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0095] Since the instructions stored in the storage medium can execute the steps in any method provided in the embodiments of the present invention, the beneficial effects of any method provided in the embodiments of the present invention can be achieved. Please refer to the previous embodiments for details and will not be repeated here.

[0096] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for improving the temperature control accuracy of chip testing, applied to a temperature control system, characterized in that: The method comprises: Obtain the temperature value of a specific position of the chip through an infrared temperature sensor; Acquire infrared images of different positions of the chip by a thermal imager, wherein the infrared images of different positions include infrared images corresponding to the specific position; Determining predicted temperature values ​​at different positions of the chip based on the temperature value at the specific position and the infrared imaging; If it is detected that the maximum value and the minimum value in the temperature prediction value are both within the preset temperature range, the difference between the maximum value and the minimum value is calculated; If it is detected that the difference exceeds a preset change threshold, the power output of the heating or cooling system is adjusted so that the difference does not exceed the preset change threshold.

2. The method according to claim 1, characterized in that The step of determining the temperature prediction values ​​of different positions of the chip based on the temperature value of the specific position and the infrared imaging specifically includes: Obtaining information about constituent materials of the chip at different locations; Determining the emissivity of the chip at different positions according to a preset emissivity table and the constituent material information, wherein the emissivity table records the emissivity corresponding to different materials; Based on the temperature value and infrared imaging at the specific position, the predicted temperature values ​​at other positions are calculated according to the emissivity.

3. The method according to claim 2, characterized in that The step of calculating the predicted temperature values ​​at other locations based on the emissivity and taking the temperature value at the specific location and the infrared imaging as a reference specifically includes: Acquire the radiation energy of the chip at different positions; The temperature prediction values ​​at other positions are calculated according to the radiation energy and the corresponding emissivity at the different positions.

4. The method according to claim 1, characterized in that: After the step of determining the temperature prediction values ​​of different positions of the chip according to the temperature value of the specific position and the infrared imaging, the method further includes: If it is detected that the maximum value or the minimum value of the temperature prediction value exceeds the preset temperature range, the power output of the heating or cooling system is adjusted so that the maximum value or the minimum value does not exceed the preset temperature range.

5. The method according to claim 1, characterized in that After the step of calculating the difference between the maximum value and the minimum value if it is detected that both the maximum value and the minimum value in the temperature prediction value are within the preset temperature range, the method further includes: If it is detected that the difference does not exceed the preset change threshold, the mean of the temperature prediction values ​​is determined as the current temperature value of the chip; Generating a temperature change curve according to the current temperature value within a first preset time; Predicting the temperature change trend of the chip within a second preset time in the future according to the temperature change curve; According to the temperature change trend, the heating or cooling system is controlled to perform temperature compensation in advance.

6. The method according to claim 1, characterized in that Before the step of obtaining the temperature value of a specific position of the chip by using an infrared temperature sensor, the method further includes: The humidity of the surrounding air and the air velocity are detected by a humidity sensor and an air velocity sensor respectively; If it is detected that the air humidity exceeds the corresponding preset humidity threshold, adjusting the voltage level of the heating plate to reduce the air humidity to below the preset humidity threshold; If it is detected that the air flow rate exceeds the corresponding preset flow rate threshold, the coolant circulation rate is adjusted to reduce the air flow rate to below the preset flow rate threshold.

7. The method according to claim 1, characterized in that After the step of obtaining infrared images of different positions of the chip by a thermal imager, the method further includes: Acquire the self-test data of the infrared temperature sensor and the thermal imager respectively after each preset interval period; If an abnormality is detected in the self-test data, an early warning message is issued.

8. A temperature control system, characterized in that: The temperature control system includes: one or more processors and memory; The memory is coupled to the one or more processors, and the memory is used to store computer program codes, wherein the computer program codes include computer instructions, and the one or more processors call the computer instructions to enable the temperature control system to execute the method according to any one of claims 1 to 7.

9. A computer-readable storage medium comprising instructions, characterized in that: When the instruction is executed on the temperature control system, the temperature control system is caused to execute the method according to any one of claims 1 to 7.

10. A computer program product, characterized in that When the computer program product runs on a temperature control system, the temperature control system is enabled to perform the method according to any one of claims 1 to 7.

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