Curved-adaptive test system for integrated circuit warpage

Abstract

A surface-adaptive integrated circuit testing system is disclosed, suitable for testing integrated circuits. The integrated circuit includes a warped surface having a first radius of curvature. The surface-adaptive integrated circuit testing system includes multiple test heads, multiple test sockets, a transfer device, and a controller. Each test head includes a contact surface having at least two distinct second radii of curvature. The multiple test sockets correspond to the test heads respectively. The transfer device is adapted to move the integrated circuit. The controller is adapted to control the transfer device according to the first radius of curvature to selectively place the integrated circuit into one of the test sockets and control the contact surface of the corresponding test head to contact the warped surface of the integrated circuit. The controller selects a test head having a second radius of curvature matching the first radius of curvature.

Description

Technical Field

[0001] A surface-adaptive integrated circuit testing system, particularly a surface-adaptive integrated circuit testing system for detecting warped integrated circuits. Prior Technology

[0002] As the semiconductor industry continues to grow its demand for high-performance computing and highly integrated systems, advanced packaging technologies (such as CoWoS, Fan-Out, MCM / SiP, etc.) have become core means to achieve improved chip performance and reduced size. These technologies typically involve the integration of multiple heterogeneous materials, including silicon wafers, packaging substrates, organic resins, and metal layers. However, due to the differences in the coefficient of thermal expansion (CTE) of each material, structural deformation occurs between materials due to the accumulation of thermal stress during high-temperature processes such as reflow soldering, molding, and curing, leading to package warpage.

[0003] Especially in multi-chip stacked structures, such as the heterogeneous integration of logic chips and memory modules in CoWoS packaging, warpage issues are more pronounced. Due to the asymmetry in material stacking, such structures experience uneven thermal stress distribution, making them prone to bending deformation during heating or cooling. As package size increases and thickness decreases, structural rigidity further decreases, weakening resistance to thermal stress and exacerbating the impact of warpage on subsequent processes.

[0004] In the integrated circuit (IC) testing phase, warpage poses a significant challenge to test equipment. Existing test equipment often employs a planar design for the test head (chuck), which cannot accommodate the irregular surface of a warped IC. This results in insufficient contact area, reduced heat transfer efficiency, and impaired heat dissipation. Furthermore, poor contact leads to unstable electrical signal transmission, further reducing test yield and reliability. To mitigate the gaps caused by warpage, current technologies generally rely on thermal interface materials (TIMs) to fill the gaps between the IC and the test head.

[0005] However, the extensive use of thermal interface materials not only increases material costs, but stress concentration during repeated pressing tests can easily lead to material damage, requiring frequent replacements, further increasing maintenance costs and reducing equipment uptime. Furthermore, thermal interface materials are prone to degradation under high-temperature cycling and mechanical pressing, resulting in decreased thermal conductivity and affecting test stability. Their thickness and uniformity are also difficult to control precisely, leading to inconsistent test results. The rigid design of traditional planar test heads cannot dynamically adapt to ICs with varying degrees of warpage, requiring frequent parameter adjustments or component replacements, increasing operational complexity and time costs, especially in ultra-thin packages or large-size wafer-level packages.

[0006] However, while relying on multilayer thermal interface materials can temporarily improve the bonding problem, the increased usage leads to higher material costs. Furthermore, during each pressing test, force tends to concentrate at the warped protrusions, causing localized damage to the thermal interface material, requiring frequent replacement, increasing maintenance costs and reducing testing capacity. In addition, the thermal interface material itself is prone to deterioration under high-temperature cycling and repeated mechanical pressing, resulting in decreased heat transfer efficiency and further affecting test stability and reliability.

[0007] Therefore, there is an urgent need for an innovative testing system to address the IC package warpage problem. This system should improve the design of testing equipment, particularly the structure of the test head, to achieve effective contact with the warped IC surface, reduce reliance on thermal interface materials, and improve testing efficiency, yield, and cost-effectiveness. This technology must not only address the shortcomings of existing equipment in terms of contact and heat conduction but also possess flexibility to adapt to diverse package shapes and degrees of warpage, thereby meeting the semiconductor testing industry's demands for high precision and high reliability. Summary of the Invention

[0008] In view of this, in some embodiments, a surface-adaptive integrated circuit testing system is provided, suitable for testing integrated circuits. The integrated circuit includes a warped surface having a first radius of curvature. The surface-adaptive integrated circuit testing system includes a plurality of test heads, a plurality of test sockets, a transfer device, and a controller. Each test head includes a contact surface having at least two distinct second radii of curvature. The plurality of test sockets correspond to the test heads respectively. The transfer device is adapted to move the integrated circuit. The controller is adapted to control the transfer device according to the first radius of curvature to selectively place the integrated circuit into one of the test sockets and control the contact surface of the corresponding test head to contact the warped surface of the integrated circuit. The controller selects a test head having a second radius of curvature matching the first radius of curvature.

[0009] In summary, the controller uses the first radius of curvature of the integrated circuit as a matching reference to select a test head whose contact surface matches the warped surface. Therefore, when the test head presses against the integrated circuit, the fit between the contact surface and the warped surface is improved, resulting in better heat dissipation and better temperature uniformity. Furthermore, the use of thermal interface material (TIM) can be reduced or replaced; in cases of good fit, TIM may even be completely unnecessary.

[0010] The following detailed description of the features and advantages of the present invention is sufficient to enable anyone skilled in the art to understand the technical content of the present invention and implement it accordingly. Based on the content disclosed in this specification, the scope of the patent application and the drawings, anyone skilled in the art can easily understand the relevant objectives and advantages of the present invention. Simple Explanation of the Diagram

[0011] Figure 1 is a schematic diagram of the architecture of the surface-adaptive integrated circuit test system in some embodiments of the present invention. Figure 2 is a schematic diagram of the transfer of integrated circuits in the surface-adaptive integrated circuit test system in some embodiments of the present invention. Figure 3 is a schematic diagram of measuring the radius of curvature of an integrated circuit using a surface-adaptive integrated circuit testing system in some embodiments of the present invention. Figure 4A is a schematic diagram of the first test head placing the integrated circuit into the test socket in some embodiments of the present invention. Figure 4B is a schematic diagram of the second test head placing the integrated circuit into the test socket in some embodiments of the present invention. Figure 4C is a schematic diagram of the third test head placing the integrated circuit into the test socket in some embodiments of the present invention. Figure 4D is a schematic diagram of the fourth test head placing the integrated circuit into the test socket in some embodiments of the present invention. Figure 5A is a temperature distribution diagram measured when the first test head is pressed against the integrated circuit in some embodiments of the present invention. Figure 5B is a temperature distribution diagram measured when the second test head is pressed against the integrated circuit in some embodiments of the present invention. Figure 5C is a temperature distribution diagram measured when the third test head is pressed against the integrated circuit in some embodiments of the present invention. Figure 5D is a temperature distribution diagram measured when the fourth test head is pressed against the integrated circuit in some embodiments of the present invention. Figure 6 is a schematic diagram of another architecture of the surface-adaptive integrated circuit test system in some embodiments of the present invention. Implementation

[0012] In some embodiments, as shown in Figures 1, 2, and 3, a surface-adaptive integrated circuit testing system (hereinafter referred to as testing system 100) is adapted to test an integrated circuit 200. The integrated circuit 200 includes a warped surface 202 having a first radius of curvature. Testing system 100 includes a plurality of test heads 102, a plurality of test sockets 104, a transfer device 106, and a controller 108. Each test head 102 includes a contact surface 110 (see contact surfaces 110 in Figures 4A to 4D), and these contact surfaces 110 include at least two distinct second radii of curvature. The plurality of test sockets 104 correspond to the respective test heads 102. The transfer device 106 is adapted to move the integrated circuit 200. The controller 108 is adapted to control the transfer device 106 according to the first radius of curvature to selectively place the integrated circuit 200 into one of the test holders 104, and to control the contact surface 110 of the corresponding test head 102 to contact the warped surface 202 of the integrated circuit 200. The controller 108 selects the test head 102 having a second radius of curvature that matches the first radius of curvature.

[0013] The integrated circuit 200 may be, for example, but not limited to, one of a central processing unit (CPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), and a tensor processing unit (TPU).

[0014] Multiple test heads 102 are adapted to move toward the test holder 104 when the integrated circuit 200 is placed in the corresponding test socket 104, pressing against the warped surface 202 of the integrated circuit 200 to ensure uniform contact between the integrated circuit 200 and the test holder 104. For example, when the integrated circuit 200 is placed in the test holder 104, the test head 102 can be actuated to move toward the test holder 104, ensuring close contact between the integrated circuit 200 and the test holder 104. When the integrated circuit 200 has completed testing, the test head 102 moves away from the test holder 104, allowing the tested integrated circuit 200 to be removed from the test holder 104 for testing the next integrated circuit 200. In some embodiments, the area of ​​the contact surface 110 of the test head 102 is substantially equal to or slightly larger than the warped surface 202. Therefore, when the test head 102 applies pressure to the integrated circuit 200, the contact surface 110 can uniformly apply pressure to the warped surface 202.

[0015] Each test socket 104 is configured with a corresponding test head 102. When each test socket 104 is actuated, a test action can be performed to test whether the integrated circuit 200 meets the specifications. The test action may be, for example, but not limited to, electrical testing or functional testing. In some embodiments, each test head 102 may be located on the same plumb line L1 as the corresponding test socket 104 (as shown in Figures 4A to 4D), and the test head 102 may be axially displaced along the plumb line L1 so that the center position of the test head 102 is coaxial with the center position of the integrated circuit 200. In some embodiments, the test head 102 may be assembled with a lifting assembly (not shown in the figures), which can drive the test head 102 to perform lifting displacement movement. The lifting assembly may be, for example, but not limited to, a combination of a lifting arm and a motor.

[0016] In some embodiments, the warped surface 202 of the integrated circuit 200 is a convex surface, and the contact surface 110 of the test head 102 is a concave surface. Here, the shape of the contact surface 110 can conform to the shape of the warped surface 202 to uniformly apply pressure to the warped surface 202. In some embodiments, the warped surface 202 may also be a concave surface, while the contact surface 110 of the test head 102 may be a convex surface.

[0017] In some embodiments, the number of test heads 102 and test sockets 104 can be determined based on the number of groups of the second radius of curvature. For example, three test heads 102 are respectively provided with two or more (e.g., three) groups of contact surfaces 110 with the second radius of curvature, and three groups of test heads 102 and test sockets 104 can be respectively provided, so that the integrated circuit 200 can be placed into the corresponding test socket 104 according to the measured first radius of curvature.

[0018] The transfer device 106 can perform displacement movements at multiple angles and transfer the integrated circuit 200 along a preset movement path during the testing process. For example, the integrated circuit 200 under test can be placed on a first carrier tray 101, and the integrated circuit 200 after testing can be placed on a second carrier tray 103 or a third carrier tray 105; the second carrier tray 103 can be a good product carrier tray, and the third carrier tray 105 can be a defective product carrier tray. During testing, the transfer device 106 can remove the integrated circuit 200 under test from the first carrier tray 101 according to a first transfer signal and move it to the corresponding test holder 104. When the test is completed, the transfer device 106 can remove it from the test holder 104 according to a second transfer signal and transfer it to the second carrier tray 103 or the third carrier tray 105 corresponding to the test result. It should be noted that the first transfer signal includes the movement path from the first carrier tray 101 to the designated test holder 104. The second transfer signal specifies the movement path from the test mount 104 to the second carrier plate 103 or the third carrier plate 105. The movement path may include spatial coordinates, enabling the transfer device 106 to move accurately according to the spatial coordinates.

[0019] In some embodiments, the transfer device 106 may include at least one robotic arm 107. The robotic arm 107 may be configured with a suction nozzle 109 to adjust the negative pressure to adsorb or release the integrated circuit 200. In other embodiments, the transfer device 106 may further include a shuttle (not shown) responsible for unidirectional displacement in a plane. For example, after the robotic arm 107 obtains the integrated circuit 200 to be tested from the first carrier plate 101, it places it into the shuttle, and the shuttle moves the integrated circuit 200 to be tested into the testing area.

[0020] The controller 108 is electrically connected to the test head 102, the test socket 104, and the transfer device 106 to actuate the test head 102, the test socket 104, and the transfer device 106. The controller 108 can determine the test head 102 having a contact surface 110 that matches the warped surface 202 based on a first radius of curvature. For example, at the start of the test operation, the controller 108 can generate a first transfer signal based on the first radius of curvature of the integrated circuit 200; then, after the integrated circuit 200 is placed in the designated test socket 104, the controller 108 actuates the test head 102 and the test socket 104; finally, the controller 108 generates a second transfer signal based on the detection result. The controller 108 may include one or more microprocessors, one or more digital signal processors, one or more memories, one or more input / output units, and one or more logic circuits capable of performing the same functions as these elements, such as an industrial computer or an automation controller.

[0021] In some embodiments, the controller 108 may perform subsequent actions after each acquisition of the first radius of curvature. The first radius of curvature of the integrated circuit 200 may be pre-stored in the controller 108, or it may be transferred to the corresponding test socket 104 based on the measured first radius of curvature after measuring the first radius of curvature of each integrated circuit 200. In other embodiments, the first radius of curvature of each integrated circuit 200 may be directly provided by the upstream wafer fabrication plant.

[0022] In some embodiments, as shown in Figures 1, 2, 4A, 4B, 4C, and 4D, the test heads 102 include a first test head 112, a second test head 114, and a third test head 116. The controller 108 can determine the test heads (112, 114, 116) having contact surfaces 110 that match the warped surface 202 based on the warp amount. The first test head 112 has a first warp amount, the second test head 114 has a second warp amount, and the first warp amount is less than the second warp amount. The third test head 116 has a third warp amount, and the third warp amount is greater than the second warp amount. In some embodiments, the test head 102 further includes a fourth test head 117, which has a fourth warp amount, and the fourth warp amount is greater than the third warp amount. Knowing the dimensions and warp amount of the integrated circuit 200, the radius of curvature can be obtained using the formula (1) described later.

[0023] In other embodiments, the controller 108 may also compare the first radius of curvature of the integrated circuit 200 with the second radius of curvature of any test head (112, 114, 116, 117) to determine the test head 102 that matches the integrated circuit 200. For example, if the first radius of curvature is close to the second radius of curvature of the first test head 112, the controller 108 may determine that the integrated circuit 200 matches the first test head 112, and control the transfer device 106 to place the integrated circuit 200 into the test seat 104 corresponding to the first test head 112. In some embodiments, the first warp of the first test head 112 is 0 mm (i.e., flat), the second warp of the second test head 114 is 0.1 mm, the third warp of the third test head 116 is 0.2 mm, and the fourth warp of the fourth test head 117 is 0.3 mm. In some embodiments, the second radius of curvature of the test head 102 contacting the warped surface 202 is greater than or equal to the first radius of curvature.

[0024] In one example, the warpage measured by integrated circuit 200 is 0.09 mm. This warpage is greater than the first warpage (0 mm) of the first test head 112, therefore the first test head 112 does not meet the matching condition. The warpage of integrated circuit 200 is close to and less than the second warpage (0.1 mm) of the second test head 114, therefore the second test head 114 meets the matching condition. On the other hand, although the warpage of integrated circuit 200 is less than the third warpage (0.2 mm) of the third test head 116 or the fourth warpage (0.3 mm) of the fourth test head 117, it is not the closest to the third or fourth warpage, therefore the third test head 116 and the fourth test head 117 do not meet the matching condition. Accordingly, controller 108 determines that the second test head 114 matches integrated circuit 200.

[0025] In some embodiments, the second radius of curvature of the contact surface 110 is greater than or equal to the first radius of curvature of the warped surface 202, or the maximum warp of the contact surface 110 is less than or equal to the maximum warp of the warped surface 202. This design aims to avoid the following problem: if the second radius of curvature of the contact surface 110 is smaller than the first radius of curvature of the warped surface 202, or if its maximum warp is greater than the maximum warp of the warped surface 202, the most warped (most bent) point of the contact surface 110 may not be able to fully conform to the warped surface 202. Typically, this most warped point is located at the centroid (center) of the warped surface 202, which is also the highest temperature region. Therefore, if the contact surface 110 cannot fully conform to the warped surface 202 at this high temperature, the heat dissipation effect will be significantly reduced.

[0026] In another example, the maximum warpage measured by the integrated circuit 200 is 0.2 mm. The first test head 112, the second test head 114, the third test head 116 and the fourth test head 117 respectively measured the actual stress value of the warped surface 202 by applying a preset pressure of 2.8 kgf / cm² (kilogram force per square centimeter) to the warped surface 202. The measurement results are shown in Table (I) below.

[0027] Table (1): Maximum warpage of contact surface Approaching 0mm (First test head) 0.1mm (Second test head) 0.2mm (Third test head) 0.3mm (Fourth test head) Maximum stress (N / mm²) 0.97 0.75 0.74 0.74 Minimum stress (N / mm²) 0.05 0.07 0.07 0.04 Mean stress (N / mm²) 0.25 0.27 0.27 0.28

[0028] The first warpage amount (0 mm) of the first test head 112 is less than the maximum warpage amount measured on the warped surface 202. This indicates that the degree of warpage of the contact surface 110 is less than that of the warped surface 202 (this could mean that the side edge of the contact surface 110 may not be in contact with the warped surface 202). Based on the stress measurement results of the warped surface 202 under pressure applied by the first test head 112, the maximum stress measured on the warped surface 202 is significantly greater than that of the second test head 114, the third test head 116, and the fourth test head 117. This indicates that the force applied by the first test head 112 to the warped surface 202 is the most uneven (concentrated at the center of the warped surface 202), which may result in greater thermal resistance. The second warpage amount (0.1 mm) of the second test head 114 is less than the maximum warpage amount measured on the warped surface 202, indicating that the degree of warpage of the contact surface 110 is less than that of the warped surface 202. According to the measurement results of the second test head 114, the difference between the maximum and minimum stress measured on the warped surface 202 is better than that of the first test head 112 and the fourth test head 117, but slightly worse than that of the third test head 116. The third warping amount (0.2 mm) of the third test head 116 is equal to the warping amount of the warped surface 202, indicating that the contact surface 110 and the warped surface 202 have the maximum fit. According to the measurement results of the second test head 114, the difference between the maximum and minimum stress measured on the warped surface 202 is better than that of the first test head 112, the second test head 114, and the fourth test head 117. This indicates that the contact surface 110 of the third test head 116 can completely fit and uniformly apply force to the warped surface 202. The fourth warping amount of the fourth test head 117 is greater than the warping amount of the warped surface 202, indicating that the degree of warping of the contact surface 110 is greater than that of the warped surface 202 (which may mean that the center of the contact surface 110 may not be in contact with the warped surface 202). According to the measurement results of the fourth test head 117, the difference between the maximum and minimum stress measured on the warped surface 202 is greater than that of the second test head 114 and the third test head 116, but better than that of the first test head 112. According to the experimental results in Table (I), the controller 108 selects the test heads (112, 114, 116, 117) with the highest fit between the contact surface 110 and the warped surface 202 by comparing the warping amount of the warped surface 202 with the warping amount of multiple contact surfaces 110.

[0029] As shown in Figures 1, 2, and 3, in some embodiments, the test system 100 further includes a three-dimensional measurement module 118. The three-dimensional measurement module 118 is electrically connected to a controller 108. The controller 108 controls the three-dimensional measurement module 118 to measure the warpage of the warped surface 202 of the integrated circuit 200. At the start of the test, the controller 108 may generate a third transfer signal. The third transfer signal includes a movement path from the first carrier plate 101 to a measurement position of the three-dimensional measurement module 118. When the integrated circuit 200 is in the measurement position, the controller 108 may actuate the three-dimensional measurement module 118. After the three-dimensional measurement module 118 completes the measurement, the controller 108 can obtain the warpage of the warped surface 202. In other embodiments, after the three-dimensional measurement module 118 completes the measurement, the controller 108 may receive the measured data (e.g., maximum warpage) to calculate a first radius of curvature. The controller 108 acquires the first radius of curvature and can then perform matching and comparison between the first radius of curvature and a plurality of second radii of curvature (or compare the amount of warpage). The three-dimensional measurement module 118 may be, for example, but not limited to, an X-ray diffractometer, a micro-Raman spectrometer, a spherometer, or a Fizeau interferometer.

[0030] In some embodiments, before the transfer device 106 places the integrated circuit 200 into the corresponding test socket 104, the controller 108 may control the transfer device 106 to transfer the integrated circuit 200 to the three-dimensional measurement module 118. After the three-dimensional measurement module 118 measures the warped surface 202 of the integrated circuit 200, the controller 108 then transfers the integrated circuit 200 to the corresponding test socket 104 according to the first radius of curvature (or the maximum warp amount).

[0031] In some embodiments, the first radius of curvature of the warped surface 202 is determined by the following formula (1):

[0032] R=(L2+W2) / (8kω)(Formula (1));

[0033] In formula (1), R is the radius of curvature (the first radius of curvature of the warped surface 202), L is the length of the warped surface 202, W is the width of the warped surface 202, k is the surface shape adjustment factor, and ω is the maximum warping of the warped surface 202.

[0034] As shown in Figure 3, the three-dimensional measurement module 118 can measure the length and width of the warped surface 202, and use a preset plane height of the warped surface 202 as a measurement reference plane 203. Based on this measurement reference plane 203, the highest and lowest points of the warped surface 202 are found, and the difference between the maximum positive deviation and the maximum negative deviation is calculated, which is the maximum warping amount.

[0035] The controller 108 can input the maximum warpage into the above formula (1) to calculate the first radius of curvature of the warped surface 202. In some embodiments, the preset plane height can be the height of the planes on both sides of the warped surface 202 (i.e., the measurement reference plane 203 in FIG3) in spatial coordinates when the warped surface 202 is set as a flat surface according to the process specifications of the integrated circuit 200. The preset plane height can also be the height of an electrical connection surface 205 in spatial coordinates of the integrated circuit 200 contacting the test base 104. The maximum warpage can be obtained by subtracting the thickness of the integrated circuit 200 from the maximum difference obtained in this way.

[0036] In some embodiments, in order to make the formula (1) closer to the actual warping distribution of the integrated circuit 200, a surface shape adjustment factor is designed to compensate for the difference between the ideal spherical model and the real situation. The value range is usually set to 0.8~1.2. In response to the relatively concentrated warping distribution of the warped surface 202, such as a local bulge or depression in the center, or the warping mainly concentrated in a certain area rather than being uniformly distributed across the entire surface, the surface shape adjustment factor is greater than 0.8 and less than 1.0. The more concentrated the warping distribution, the closer it is to 0.8. In response to the relatively uniform warping distribution of the warped surface 202, such as a relatively uniform and gentle surface warping distribution, that is, the warping amount is distributed over a large area and the curvature is not obvious, or the overall curvature is biased towards a large radius of curvature (closer to a plane), the surface shape adjustment factor is less than 1.2 and greater than 1.0. The more uniform and gentle the warping distribution, the closer it is to 1.2. Therefore, the controller 108 can select the corresponding surface shape adjustment factor according to the warping distribution of the warped surface 202, so that the measured radius of curvature is closer to the actual situation.

[0037] In some embodiments, the integrated circuit 200 is sized as 50mm (length) * 50mm (width) as an example. According to formula (1), if the first warpage of the contact surface 110 of the first test head 112 is 0mm, the second radius of curvature of the first test head 112 approaches infinity, i.e., close to a plane; if the second warpage of the contact surface 110 of the second test head 114 is 0.1mm, the range of the second radius of curvature of the second test head 114 is between 5200mm and 7800mm; if the third warpage of the contact surface 110 of the third test head 116 is 0.2mm, the range of the second radius of curvature of the third test head 116 is between 2600mm and 3900mm. Here, the controller 108 can also compare the range of the second radius of curvature with the first radius of curvature. If the first radius of curvature matches the range of the second radius of curvature of one of the test heads (112, 114, 116), then the controller 108 transfers the integrated circuit 200 to the corresponding test head 102. In some embodiments, the three-dimensional measurement module 118 can also measure the first radius of curvature using an osculating circle fitting method. For example, at a specific point or region on the measured model, an arc that best fits the surface is fitted, and the radius of the arc is the radius of curvature of that point or region.

[0038] The aforementioned measurement methods can all measure the first radius of curvature through the controller 108 and / or the three-dimensional measurement module 118. The test system 100 can select a suitable measurement method based on the three-dimensional measurement module 118.

[0039] In some embodiments, as shown in Figures 1, 4A, 4B, 4C, and 4D, the test system 100 further includes a temperature control module 120. The temperature control module 120 is adapted to regulate the temperature of the integrated circuit 200 through the test head 102. Here, during the testing of the integrated circuit 200 by the test socket 104, the temperature control module 120 can control the temperature of the integrated circuit 200 within its operating temperature range to prevent damage to the integrated circuit 200 during the test. Alternatively, the controller 108 can also collect the adjusted temperature distribution of the integrated circuit 200 to confirm whether the integrated circuit 200 is functioning properly.

[0040] In some examples, the test system 100 can perform temperature tests on the integrated circuit 200. The test head 102 can conduct heat energy through the warped surface 202 to perform high-temperature tests or pre-burn-in tests on the integrated circuit 200. The following example illustrates the warping of the first radius of curvature of the integrated circuit 200 as 0.2 mm.

[0041] Figure 5A shows the temperature distribution after the contact surface 110 of the first test head 112 (with a first warp of 0 mm) contacts and is pressed against the warped surface 202 of the integrated circuit 200 (with a warp of 0.2 mm). On the other hand, the second radius of curvature of the contact surface 110 is greater than the first radius of curvature of the warped surface 202; therefore, the temperature of the first test head 112 near its center gradually increases towards the sides (as shown by temperature trend curve L2a in Figure 5A). The highest temperature measured by the first test head 112 is 30.19 degrees Celsius, the lowest temperature is 29.82 degrees Celsius, the temperature difference is 0.37 degrees Celsius, and the thermal resistance is approximately 0.0085°C / W. Thus, the first test head 112 only contacts the warped surface 202 near its center and its surrounding area, resulting in a lower temperature around the center of the warped surface 202 compared to other locations. It should be noted that the center position of the first test head 112 is determined according to the temperature measurement position of the integrated circuit 200, and the center position in Figure 5A is approximately the position corresponding to the X-axis -20mm.

[0042] Figure 5B shows the temperature distribution after the contact surface 110 of the second test head 114 (with a second warp of 0.1 mm) comes into contact with and is pressed against the warped surface 202 of the integrated circuit 200 (with a warp of 0.2 mm). On the other hand, the second radius of curvature of the contact surface 110 is greater than the first radius of curvature of the warped surface 202; therefore, the temperature is relatively low near the center (approximately between -50 mm and -40 mm along the X-axis), and gradually increases with increasing distance towards the sides (as shown by temperature trend curve L2b in Figure 5B). Measurement results show that the temperature ranges from 29.85°C to 30.18°C, with the highest temperature measured by the first test head 112 being 30.18°C and the lowest being 29.85°C, a temperature difference of 0.33°C, and a thermal resistance of approximately 0.0051°C / W. As can be seen, compared with the contact pattern shown in Figure 5A, the contact pattern in Figure 5B forms a narrower temperature distribution range and a flatter temperature trend curve L2b, showing a superior temperature control effect.

[0043] Figure 5C shows the temperature distribution after the contact surface 110 (warpage of 0.2 mm) of the third test head 116 contacts and is pressed against the warped surface 202 (warpage of 0.2 mm) of the integrated circuit 200. Furthermore, the radii of curvature of the contact surface 110 and the warped surface 202 are approximately the same, allowing them to almost completely adhere. Therefore, the temperature distribution from the center of the third test head 116 (approximately between -10 mm and 0 mm on the X-axis in Figure 5C) to the sides is consistent (as shown by temperature trend curve L2c in Figure 5C). The highest temperature measured by the third test head 116 is 25.99 degrees Celsius, the lowest is 25.97 degrees Celsius, the temperature difference is 0.02 degrees Celsius, and the thermal resistance is approximately 0.0015°C / W. The third test head 116 exhibits significantly better temperature control compared to the first test head 112, the second test head 114, and the fourth test head 117.

[0044] Figure 5D shows the temperature distribution after the contact surface 110 of the fourth test head 117 (with a fourth warp of 0.3 mm) comes into contact with and is pressed against the warped surface 202 of the integrated circuit 200 (with a warp of 0.2 mm). On the other hand, the second radius of curvature of the contact surface 110 is smaller than the first radius of curvature of the warped surface 202; therefore, the temperature at the center of the fourth test head 117 (approximately 0 mm on the X-axis in Figure 5D) is higher than the temperature on the sides (as shown by the temperature trend curve L2d in Figure 5D). The highest temperature measured by the fourth test head 117 is 29.99 degrees Celsius, the lowest temperature is 29.67 degrees Celsius, and the thermal resistance is approximately 0.0049°C / W. Overall, the temperature control effect is still better than that of the first test head 112 shown in Figure 5A.

[0045] According to the temperature measurement distribution diagrams in Figures 5A to 5D, if the warpage of the first radius of curvature is 0.2 mm, the third test head 116 has a better cooling effect and cooling range compared to other test heads (112, 114, 117). Therefore, the controller 108, through the matching condition of the first radius of curvature and the second radius of curvature (or by comparing the warpage), ensures that the contact surface 110 and the warped surface 202 have the maximum contact range, resulting in the warped surface 202 having a better heat dissipation effect and range.

[0046] In some embodiments, as shown in Figures 4A, 4B, 4C, and 4D, the test system 100 further includes a thermal interface material 122. The thermal interface material 122 is disposed on the contact surface 110 of the test head 102. Here, the thermal interface material 122 can be used to fill gaps between the contact surface 110 and the warped surface 202 that are not fully fitted, thereby reducing thermal resistance and improving the cooling effect on the integrated circuit 200.

[0047] In some embodiments, as shown in FIG6, the test system 100 further includes a storage module 124. The storage module 124 is electrically connected to the controller 108 and pre-stores a first radius of curvature of the warped surface 202 of the integrated circuit 200. Here, the controller 108 can directly obtain the first radius of curvature from the storage module 124 without measurement through the three-dimensional measurement module 118. The storage module 124 can also pre-store a second radius of curvature for each test head (112, 114, 116, 117). When the controller 108 compares the first and second radii of curvature, it can load the data stored in the storage module 124 for comparison. The storage module 124 is a module that stores information in an electrical, magnetic, or optical manner, including a hard disk, random access memory (RAM), and read-only memory (ROM).

[0048] In summary, the controller 108 uses the actual first radius of curvature (or warp amount) of the warped surface 202 of the integrated circuit 200 as a matching reference, and selects the test head 102 with the highest contact degree between the contact surface 110 and the warped surface 202 from the second radius of curvature (or warp amount) of each test head 102. This improves the contact degree between the contact surface 110 and the warped surface 202, ensuring good contact between the contact surface 110 of the test head 102 and the warped surface 202 of the integrated circuit 200, thereby reducing thermal resistance and improving temperature uniformity, achieving superior temperature control.

[0049] The embodiments described above are only for illustrating the technical ideas and features of this case. Their purpose is to enable those skilled in the art to understand the content of this case and implement it accordingly. They should not be used to limit the scope of the patent in this case. That is, all equivalent changes or modifications made in accordance with the spirit disclosed in this case should still be covered within the scope of the patent application in this case.

[0050] 100: Test System 101: First bearing plate 102: Test Head 103: Second bearing plate 104: Test socket 105: Third bearing plate 106: Transfer device 107: Robotic Arm 108: Controller 109: Suction nozzle 110: Contact Surface 112: First test head 114: Second test head 116: Third test head 117: Fourth Test Head 118: 3D Measurement Module 120: Temperature control module 122: Thermal interface materials 124: Storage Module 200: Integrated Circuits 202: Warped Surface 203: Measurement reference surface 205: Electrical connection surface L1: Plumb line L2a, L2b, L2c, L2d: Temperature trend curves

Claims

1. A surface-adaptive integrated circuit testing system, suitable for testing an integrated circuit including a warped surface having a first radius of curvature, the surface-adaptive integrated circuit testing system comprising: Multiple test heads, each of which includes a contact surface, the contact surfaces including at least two distinct second radii of curvature; Multiple test sockets, each corresponding to a test head; a transfer device adapted to move the integrated circuit; and a controller adapted to control the transfer device according to the first radius of curvature to selectively place the integrated circuit into one of the test sockets and control the contact surface of the corresponding test head to contact the warped surface of the integrated circuit; wherein the controller selects the test head having a second radius of curvature that matches the first radius of curvature.

2. The surface-adaptive integrated circuit test system as described in claim 1, wherein, The second radius of curvature of the contact surface that contacts the warped surface is greater than or equal to the first radius of curvature.

3. The surface-adaptive integrated circuit test system as described in claim 1, wherein, The maximum warpage of one of the contact surfaces that contacts the warped surface is less than or equal to the maximum warpage of the warped surface.

4. The surface-adaptive integrated circuit test system as described in claim 3, wherein, The plurality of test heads includes a first test head, a second test head, and a third test head; the maximum warpage of the contact surface of the first test head is 0; the maximum warpage of the contact surface of the second test head is 0.1 mm; and the maximum warpage of the contact surface of the third test head is 0.2 mm.

5. The surface-adaptive integrated circuit test system as described in claim 2, wherein, The first radius of curvature of the warped surface is obtained by the following formula: R=(L2+W2) / (8kω); where R is the first radius of curvature, L is the length of the warped surface, W is the width of the warped surface, k is a surface shape adjustment factor, and ω is a maximum warping amount of the warped surface.

6. The surface-adaptive integrated circuit test system as described in claim 5, wherein, The surface shape adjustment factor is between 0.8 and 1.2; the more concentrated the warp distribution of the warped surface, the closer the surface shape adjustment factor is to 0.8; the more uniform the warp distribution of the warped surface, the closer the surface shape adjustment factor is to 1.

2.

7. The surface-adaptive integrated circuit test system as described in claim 6, wherein, The test heads include a first test head, a second test head, and a third test head; the second radius of curvature of the contact surface of the first test head approaches infinity; the second radius of curvature of the contact surface of the second test head ranges from 5200 mm to 7800 mm; and the second radius of curvature of the contact surface of the third test head ranges from 2600 mm to 3900 mm.

8. The surface-adaptive integrated circuit test system as claimed in claim 1, further comprising a storage module electrically connected to the controller, the storage module pre-storing the first radius of curvature of the warped surface of the integrated circuit.

9. The surface-adaptive integrated circuit test system as described in claim 1, further comprising: A temperature control module, suitable for regulating the temperature of the integrated circuit through the test head.

10. The surface-adaptive integrated circuit test system as described in claim 1, further comprising: A three-dimensional measurement module is electrically connected to the controller; The controller controls the three-dimensional measurement module to measure the warped surface of the integrated circuit to obtain the first radius of curvature.

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