A method of packaging a semiconductor device

Abstract

The application provides a packaging method of a semiconductor device, which comprises the following steps: welding a chip to a DBC by using solder with a melting point T1, welding an NTC to the DBC by using solder with a melting point T2, and obtaining a DBC welding assembly; T1-T2 is greater than or equal to 20 DEG C; using a bottom plate welding tool, which comprises a base and at least one NTC welding correction assembly; fixing a heat dissipation bottom plate to the base, placing the solder with the melting point T2 and the DBC welding assembly on the heat dissipation bottom plate; installing the NTC welding correction assembly to a corresponding position of a side wall of the base; and heating the clamped bottom plate welding tool according to a standard temperature curve of the heat dissipation bottom plate welding to perform reflow soldering. The method adjusts the melting point of the NTC solder, so that the NTC solder is synchronously melted with the bottom plate solder; and a detachable correction device is additionally arranged on the original bottom plate welding tool, so that the bottom plate welding and the NTC defect repairing are completed at one time, an independent repairing process is not needed, additional thermal shock can be avoided, and the repairing efficiency and the welding consistency are improved.

Description

Technical Field

[0001] This invention belongs to the technical field of semiconductor device packaging methods, and specifically relates to a semiconductor device packaging method. Background Technology

[0002] The NTC thermistor is the core temperature sensing element inside the IGBT module, directly soldered to the surface of the DBC substrate for real-time monitoring of the module's junction temperature. The current mainstream packaging process completes the core soldering in two steps: 1. DBC chip soldering: The power chip and NTC are simultaneously mounted and reflow soldered on the DBC substrate. In this step, the same high-temperature solder is typically used for both the chip and NTC to ensure reliable soldering. 2. Baseplate soldering: The DBC assembly with the soldered chip and NTC is then soldered to the heat sink baseplate using a solder with a lower melting point. The peak temperature only melts the baseplate solder, preventing remelting and misalignment of the chip solder joints.

[0003] Due to the small size of NTC components and pads, and the fact that DBC chip soldering processes generally do not utilize dedicated NTC positioning fixtures, placement deviations and uneven solder wetting tension during reflow can lead to NTCs exhibiting issues such as one end lifting, horizontal misalignment, and angular skew. Excessive deviations can result in NTC cold solder joint defects. Currently, the industry employs two main measures to address these NTC soldering defects: 1. Pre-positioning with fixtures: This involves using positioning slots, limit frames, and adhesive pre-fixation to restrict NTC displacement before the initial soldering. Pre-positioning with fixtures is a front-end yield improvement solution that effectively reduces defects, but it requires an additional fixture placement step, increasing production line complexity, and cannot repair existing defects. 2. Manual rework: Defective NTCs are manually cut off, residual solder is cleaned, and the NTC is remounted and then reflowed for a second soldering. Manual rework is redundant, inefficient, and results in large fluctuations in rework yield and a high rate of secondary solder joint defects. Furthermore, rework in a separate reflow oven adds an extra thermal cycle to the already soldered chip and DBC, exacerbating the thermal stress mismatch between the ceramic and copper layers and reducing reliability. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a semiconductor device packaging method. By optimizing the solder system and improving the tooling structure, the NTC defect repair and the base plate welding process are deeply coupled: on the one hand, the melting point of the NTC solder is adjusted so that it melts synchronously with the base plate solder; on the other hand, a detachable straightening device is added to the original base plate welding tooling, so that the base plate welding and NTC defect repair are completed in one reflow, without the need for additional independent rework process, avoiding additional thermal shock, and greatly improving rework efficiency and welding consistency.

[0005] To address the above problems, the present invention provides a semiconductor device packaging method, comprising the following steps: S1. Solder the chip to the DBC substrate using solder with a melting point of T1, and solder the NTC to the DBC substrate using solder with a melting point of T2 to obtain the DBC soldering assembly; T1-T2≥20℃; S2. A base plate welding fixture is used, the base plate welding fixture includes: a base and at least one NTC welding correction component; the heat dissipation base plate is fixed to the base, and solder with a melting point of T2 and DBC welding component are placed on the heat dissipation base plate in sequence, and the heat dissipation base plate is fixed to the DBC welding component through the base; S3. Install the NTC welding straightening assembly to the corresponding position on the side wall of the base. The NTC welding straightening assembly includes: a horizontal mounting arm, a guide portion, a straightening block, and an elastic element. One end of the horizontal mounting arm is connected to the side wall of the base, and the guide portion is connected to the other end of the horizontal mounting arm. The guide portion can only move relative to the horizontal mounting arm in a direction perpendicular to the horizontal mounting arm. The straightening block is located at the bottom of the guide portion. The bottom of the straightening block has a cavity with an open bottom end, and the cavity is frustum-shaped. The other end of the horizontal mounting arm extends above the DBC and positions the straightening block above the NTC. The elastic element is located on the guide portion and between the bottom surface of the horizontal mounting arm and the top surface of the straightening block. The elastic element is configured to apply a downward force to the straightening block. The inner wall of the cavity of the straightening block contacts the NTC. S4. The assembled base plate welding fixture is heated according to the standard temperature curve for heat dissipation base plate welding and then reflow soldered.

[0006] Preferably, one end of the horizontal mounting arm is provided with a guide hole; the guide part is a guide post; the guide post passes through the guide hole and is in a small clearance sliding fit with the guide hole; the guide hole is provided with an anti-rotation protrusion, and the guide post is provided with an anti-rotation notch correspondingly, the anti-rotation notch and the anti-rotation protrusion cooperate to prevent the horizontal rotation of the guide post; the top end of the guide post is provided with a limiting pin to restrict the top end of the guide post from coming out of the guide hole.

[0007] Preferably, the elastic element is a compression spring; the compression spring is sleeved on the outside of the guide post and is coaxially arranged with the guide post; the upper end of the compression spring abuts against the bottom surface of the horizontal mounting arm, and the lower end of the compression spring abuts against the top surface of the straightening block.

[0008] Preferably, the angle between the sidewall of the cavity of the corrective pressure block and the vertical direction satisfies the following condition: in, The angle between the sidewall of the cavity of the corrective block and the vertical direction; H represents the maximum offset of one side of the NTC; V represents the effective vertical downward stroke of the correction block; The coefficient of friction between the NTC package surface and the straightening block; The coefficient of friction between the NTC electrode and the DBC substrate under molten solder lubrication.

[0009] Preferably, the spring stiffness of the compression spring satisfies the following condition: k≤F / ; Where k is the spring stiffness of the compression spring; F represents the destructive load of the NTC; This refers to the working compression of the spring.

[0010] Preferably, the side of the corrective block is provided with a plurality of vent holes penetrating the side wall of the corrective block, and the vent holes are in communication with the cavity.

[0011] Preferably, the vent is located at the top or upper side wall of the cavity of the correcting block.

[0012] Preferably, the horizontal mounting arm is made of stainless steel or titanium alloy.

[0013] Preferably, the material of the corrective pressure block is alumina ceramic or aluminum nitride ceramic.

[0014] Preferably, the top of the side wall of the base is provided with a rectangular groove; one end of the horizontal mounting arm is embedded in the rectangular groove and is detachably connected to the rectangular groove by a positioning pin.

[0015] Compared with the prior art, the present invention has the following advantages: The semiconductor device packaging method of this invention deeply couples NTC defect repair with the base plate welding process through a combination of solder system optimization and tooling structure improvement: on the one hand, the melting point of the NTC solder is adjusted so that it melts synchronously with the base plate solder; on the other hand, a detachable NTC welding correction component is added to the original base plate welding tooling, so that base plate welding and NTC defect repair are completed in one reflow, eliminating redundant steps of manual rework and improving rework efficiency several times; no separate reflow is required, avoiding the DBC and chip undergoing an extra thermal cycle, reducing thermal stress mismatch between the ceramic layer and the copper layer, reducing the risk of DBC delamination, and improving the long-term reliability of the module; the use of mechanized tooling correction eliminates individual differences in manual operation, and the correction position accuracy and welding consistency are much higher than those of manual rework, significantly reducing yield fluctuations. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the base plate welding fixture in the semiconductor device packaging method according to an embodiment of the present invention; Figure 2 This is a cross-sectional view of the NTC welding correction component in the semiconductor device packaging method according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the base of the bottom plate welding fixture in the semiconductor device packaging method according to an embodiment of the present invention; Figure 4 This is a force analysis diagram of the straightening pressure block and NTC in an embodiment of the present invention; Figure 5 This is a diagram showing the travel distance of the correction block and the NTC correction circuit in an embodiment of the present invention; Figure 6 This is a schematic diagram of the guide portion in the NTC welding straightening assembly of the semiconductor device packaging method described in this embodiment of the invention.

[0017] Wherein: 1-Horizontal mounting arm; 2-Guide part; 3-Correcting pressure block; 4-Elastic element; 5-Base; 6-Cavity; 7-Guide hole; 8-Anti-rotation notch; 9-Anti-rotation protrusion; 10-Limit pin; 11-Exhaust hole; 12-Positioning pin; 13-Rectangular groove; 14-NTC; 15-DBC; 16-Boss structure; 17-Heat dissipation base plate. Detailed Implementation

[0018] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1 The power device packaging method of this embodiment includes the following steps: S1. Using solder with a melting point of T1, the chip is soldered onto the DBC substrate, and using solder with a melting point of T2, the NTC is soldered onto the DBC substrate to obtain the DBC soldering assembly; T1 T2≥20℃; S2. A base plate welding fixture is adopted, which includes: a base 5 and at least one NTC welding correction component; the heat dissipation base plate 17 is fixed to the base 5, and solder with a melting point of T2 and DBC welding component are placed on the heat dissipation base plate 17 in sequence, and the heat dissipation base plate 17 and DBC welding component are fixed by the base 5. S3. Install the NTC welding correction assembly to the corresponding position on the side wall of the base, such as... Figure 1 , 2As shown in Figure 3, the NTC welding straightening assembly includes: a horizontal mounting arm 1, a guide portion 2, a straightening block 3, and an elastic element 4; one end of the horizontal mounting arm 1 is connected to the side wall of the base 5, the guide portion 2 is connected to the other end of the horizontal mounting arm 1, and the guide portion 2 can only move relative to the horizontal mounting arm 1 in a direction perpendicular to the horizontal mounting arm 1; the straightening block 3 is located at the bottom of the guide portion 2; the bottom of the straightening block 3 has a cavity 6 with an open bottom end, and the cavity 6 is a truncated quadrangular shape; the other end of the horizontal mounting arm 1 extends above the DBC 15, and positions the straightening block 3 above the NTC 14; the elastic element 4 is located on the guide portion 2, between the bottom surface of the horizontal mounting arm 1 and the top surface of the straightening block 3, and the elastic element 4 is configured to apply a downward force to the straightening block 3; the inner wall of the cavity 6 of the straightening block 3 is in contact with the NTC; S4. The assembled base plate welding fixture is heated according to the standard temperature curve for heat dissipation base plate welding and then reflow soldered.

[0020] The semiconductor device packaging method of this invention employs an NTC welding correction assembly in its base plate welding fixture. During reflow soldering, after the NTC solder melts, the correction head continuously presses down under the elastic force of the elastic element. The guide slope of the cavity sidewall of the correction block converts the vertical downward pressure into a horizontal correction force, pushing the NTC to the correct position. This ensures sufficient solder wetting and resolves issues such as NTC end lifting, horizontal position deviation, and angular skew, thereby enabling defect repair of the NTC welding. When the correction block presses down, the upward reaction force generated on the horizontal mounting arm creates a torque at the connection between the horizontal mounting arm and the base, preventing the entire correction assembly from moving upward. Furthermore, only a detachable correction unit is added to the sidewall of the fixture, without altering the original positioning reference and cavity structure, making it fully compatible with existing welding processes.

[0021] The semiconductor device packaging method of this invention uses high-melting-point solder to weld the power chip to the DBC substrate, and uses the same medium-melting-point solder as the subsequent base plate welding to mount and weld the NTC. After the heat sink base plate and DBC substrate are positioned and installed, during reflow soldering, the temperature is increased according to the standard temperature curve for base plate welding. When the temperature rises above T2 and below T1, the NTC solder and the base plate solder melt synchronously. The straightening head continuously presses down under the action of elastic force, and the vertical downward pressure is converted into a horizontal correction force through the guide slope, pushing the NTC to the correct position, and the solder fully wets to complete the defect repair. During this process, the chip solder remains solid and its position is not affected. In step S2, when the heat sink base plate and DBC welding assembly are accurately positioned by the tooling base, the straightening unit is not installed, there is no structural interference, and the workpiece loading and unloading operation is completely consistent with the original process.

[0022] In summary, the semiconductor device packaging method of this invention, through a combination of solder system optimization and tooling structure improvement, deeply couples NTC defect repair with the baseboard soldering process: on the one hand, the melting point of the NTC solder is adjusted to melt synchronously with the baseboard solder; on the other hand, a detachable NTC soldering correction component is added to the original baseboard soldering tooling, completing baseboard soldering and NTC defect repair simultaneously in one reflow, eliminating redundant steps of manual rework and improving rework efficiency several times over; no separate reflow is required, avoiding an extra thermal cycle for the DBC and the chip, reducing thermal stress mismatch between the ceramic layer and the copper layer, reducing the risk of DBC delamination, and improving the long-term reliability of the module; the use of mechanized tooling correction eliminates individual differences in manual operation, and the correction position accuracy and soldering consistency are far superior to manual rework, significantly reducing yield fluctuations.

[0023] Preferably, one end of the horizontal mounting arm 1 is provided with a guide hole 7; the guide part 2 is a guide post; the guide post passes through the guide hole 7 and has a small clearance sliding fit with the guide hole 7; the guide hole 7 is provided with an anti-rotation protrusion 9, such as... Figure 6 As shown, the guide post is provided with a corresponding anti-rotation notch 8, which cooperates with the anti-rotation protrusion 9 to prevent the horizontal rotation of the guide post; the top of the guide post is provided with a limiting pin 10, which can prevent the top of the guide post from coming out of the guide hole 7, and prevent the pressure block from falling off when installing the straightening component on the base. The limiting pin can be removed before welding. The guide post can provide precise vertical movement guidance for the straightening pressure block and limit horizontal movement; the cooperation of the anti-rotation notch and the anti-rotation protrusion can prevent the horizontal angular rotation of the straightening pressure block.

[0024] Preferably, the elastic element 4 is a compression spring; the compression spring is sleeved on the outside of the guide post and coaxially arranged with the guide post; the upper end of the compression spring abuts against the bottom surface of the horizontal mounting arm, and the lower end of the compression spring abuts against the top surface of the straightening block. Further, the compression spring is a high-temperature resistant cylindrical helical compression spring. In its free state, the compression spring pushes the straightening block to its lower limit of stroke; after installation, it is compressed, providing a stable preload to the NTC. Optionally, the elastic element can also be a miniature high-temperature cylinder or a piezoelectric ceramic actuator to achieve active control of the pressing timing and pressure.

[0025] The cavity of the corrective pressure block is a frustum shape, which is a three-dimensional shape formed by cutting off the top of a four-sided pyramid with a plane parallel to the base of the pyramid. The lower opening edge is a guide slope that tapers inward, forming a funnel-shaped entrance that is wider at the outside and narrower at the inside. This can convert the vertical downward pressure into a horizontal corrective force. During the downward pressing process, the slope first contacts the offset and tilted NTC, and pushes it to the center as it moves downward, simultaneously completing the offset correction, angle alignment, and warping flattening.

[0026] Among them, the guide slope angle of the cavity of the correcting block 3 (i.e., the angle between the side wall of the cavity of the correcting block that applies force to the NTC and the vertical direction). Both the mechanically permissible condition and the travel coverage condition must be satisfied simultaneously. Specifically: a. The force on the straightening block and NTC is as follows Figure 4 As shown, the force equilibrium equations are listed respectively:

[0027]

[0028] ,

[0029]

[0030] when At that time, NTC can be driven, and simplification yields... Maximum value: .

[0031] in, To correct the angle between the guide slope of the pressure block and the vertical direction (correct the angle between the side wall of the cavity of the pressure block that applies force to the NTC and the vertical direction). The tangential pressure between the NTC and the straightening block; The friction between the NTC package surface and the straightening block; To correct the downward pressure of the pressure block; To correct the downward vertical force on the NTC caused by the pressure block; The coefficient of friction between the NTC electrode and the DBC substrate under molten solder lubrication; The coefficient of friction between the NTC package surface and the straightening block; The frictional force between the NTC electrode and the DBC substrate under molten solder lubrication; To correct the force that drives the NTC to move horizontally; Guide slope angle The larger the value, the smaller the horizontal correction force. To ensure that the NTC can be horizontally pushed in the molten state, therefore... Cannot exceed the upper limit ; b. such as Figure 5 The relationship between the downward displacement of the correction block and the correctable offset is as follows:

[0032] in, This represents the horizontal displacement of the NTC. To correct the vertical displacement of the pressure block; Guide slope angle The smaller the value, the smaller the maximum correction amount; to ensure coverage of the maximum NTC offset, therefore It cannot be less than the lower limit ;

[0033] in, H This represents the maximum offset on one side of the NTC. V To correct the effective vertical downward stroke of the pressure block.

[0034] Therefore, the final design perspective Values ​​in and between.

[0035] Preferably, the angle between the sidewall of the cavity of the straightening block and the vertical direction satisfies the following condition: , in, To correct the angle between the sidewall of the cavity of the pressure block and the vertical direction; H represents the maximum offset of one side of the NTC; V represents the effective vertical downward stroke of the correction block; The coefficient of friction between the NTC's packaging surface and the straightening block; The coefficient of friction between the NTC and DBC substrates under molten solder lubrication.

[0036] The spring compression force must be sufficient to prevent the NTC from being crushed; it must follow Hooke's Law: F=k Δx; where F is the compressive force of the straightening block, k is the spring stiffness, and Δx is the working compression of the spring.

[0037] Preferably, the spring stiffness of the compression spring satisfies the following condition: k≤F / ; Where k is the spring stiffness of the compression spring; F represents the destructive load of the NTC; This refers to the working compression of the spring.

[0038] This invention further derives a quantitative design formula for the slope angle and spring force, which can flexibly adjust parameters according to different NTC sizes and different production line defect levels, covering multiple series of modular products.

[0039] Preferably, the straightening block 3 has multiple vent holes 11 penetrating the side wall of the straightening block, and the vent holes 11 communicate with the cavity 6. The vent holes 11 penetrate the wall thickness of the straightening block, connecting the lower cavity of the straightening block to the outside. During reflow soldering, the flux vapors released by the melting solder are smoothly discharged through the vent holes, avoiding gas accumulation between the straightening block and the NTC and DBC, thereby preventing solder void defects and secondary NTC displacement caused by gas pressure.

[0040] Preferably, the vent 11 is located at the top or high on the side wall of the cavity 6 of the straightening block to ensure that the air passage is not blocked during the solder filling process.

[0041] Preferably, the horizontal mounting arm 1 is made of stainless steel or titanium alloy. This minimizes deformation at high temperatures, ensuring accurate pressing positions.

[0042] Preferably, the straightening block 3 is made of alumina ceramic or aluminum nitride ceramic. It is heat-resistant, non-stick to solder, and has good insulation properties. More preferably, the straightening block 3 is integrally formed.

[0043] Preferably, the top of the side wall of the base 5 is provided with a rectangular groove 13; one end of the horizontal mounting arm 1 is embedded in the rectangular groove 13 and is detachably connected to the rectangular groove 13 by a positioning pin 12. The NTC welding straightening assembly can be quickly assembled and disassembled without affecting other workstations or the functions of existing tooling. When the straightening block is pressed down, the upward reaction force generated on the horizontal mounting arm forms a torque on the positioning pin 12, preventing the entire straightening assembly from moving upward.

[0044] Optionally, the melting point of the NTC solder can be slightly lower than that of the heat sink solder by 5~10°C, allowing for a longer correction time window, which is still within the scope of the present invention.

[0045] Preferably, after step S4, the method further includes: S5. After the solder has completely solidified, it is cooled in the reflow oven cooling chamber and the tooling is removed.

[0046] Example 2 This embodiment is applied to the vacuum reflow soldering process of the base plate of an IGBT module. The NTC body is a cylindrical structure with a diameter of 2mm and a length of 3.2mm. The destructive load... The original production line has a maximum single-sided offset of 1.5mm for NTC; the base plate welding fixture described above is used, and the structural parameters of the NTC welding correction component are as follows.

[0047] 1. Solder system configuration The chip DBC solder uses SnSb5 high-temperature solder with a melting point of [missing information]. The NTC-DBC solder and DBC-baseplate solder use SAC305 solder, with a melting point of [missing information]. The melting point difference is 23℃, which meets the design criterion of ≥20℃; the peak welding temperature of the base plate is set to 230℃, which is between the two melting points.

[0048] 2. NTC Welding Straightening Component Parameter Design (1) Angle of the guide slope The straightening clamp is made of 95% alumina ceramic, and its friction coefficient with the NTC borosilicate glass encapsulation surface is [missing information]. ; The coefficient of friction between NTC electrode and DBC under molten SnSb5 solder lubrication ; Calculated ; The effective vertical downward stroke of the pressure block is , needs to be covered The offset is calculated. ; Therefore, select .

[0049] (2) Spring compression force design The safety factor is taken as 5.88, and the working pressure is... .

[0050] Spring working compression The spring stiffness is calculated as follows: .

[0051] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for packaging a semiconductor device, characterized in that, Includes the following steps: S1. Using solder with a melting point of T1, the chip is soldered onto the DBC substrate, and using solder with a melting point of T2, the NTC is soldered onto the DBC substrate to obtain the DBC soldering assembly; T1 T2≥20℃; S2. A base plate welding fixture is used, the base plate welding fixture includes: a base and at least one NTC welding correction component; the heat dissipation base plate is fixed to the base, and solder with a melting point of T2 and DBC welding component are placed on the heat dissipation base plate in sequence, and the heat dissipation base plate is fixed to the DBC welding component through the base; S3. Install the NTC welding straightening assembly to the corresponding position on the side wall of the base. The NTC welding straightening assembly includes: a horizontal mounting arm, a guide portion, a straightening block, and an elastic element. One end of the horizontal mounting arm is connected to the side wall of the base, and the guide portion is connected to the other end of the horizontal mounting arm. The guide portion can only move relative to the horizontal mounting arm in a direction perpendicular to the horizontal mounting arm. The straightening block is located at the bottom of the guide portion. The bottom of the straightening block has a cavity with an open bottom end, and the cavity is frustum-shaped. The other end of the horizontal mounting arm extends above the DBC and positions the straightening block above the NTC. The elastic element is located on the guide portion and between the bottom surface of the horizontal mounting arm and the top surface of the straightening block. The elastic element is configured to apply a downward force to the straightening block. The inner wall of the cavity of the straightening block contacts the NTC. S4. The assembled base plate welding fixture is heated according to the standard temperature curve for heat dissipation base plate welding and then reflow soldered.

2. The semiconductor device packaging method according to claim 1, characterized in that: One end of the horizontal mounting arm is provided with a guide hole; the guide part is a guide post; the guide post passes through the guide hole and is in a small clearance sliding fit with the guide hole; the guide hole is provided with an anti-rotation protrusion, and the guide post is provided with an anti-rotation notch correspondingly, the anti-rotation notch and the anti-rotation protrusion cooperate to prevent the horizontal rotation of the guide post; the top end of the guide post is provided with a limiting pin to restrict the top end of the guide post from coming out of the guide hole.

3. The semiconductor device packaging method according to claim 2, characterized in that: The elastic element is a compression spring; the compression spring is sleeved on the outside of the guide post and is coaxially arranged with the guide post; the upper end of the compression spring abuts against the bottom surface of the horizontal mounting arm, and the lower end of the compression spring abuts against the top surface of the straightening block.

4. The semiconductor device packaging method according to claim 1, characterized in that: The angle between the sidewall of the cavity of the corrective pressure block and the vertical direction satisfies the following condition: , in, The angle between the sidewall of the cavity of the corrective block and the vertical direction; H represents the maximum offset of one side of the NTC; V represents the effective vertical downward stroke of the correction block; The coefficient of friction between the NTC package surface and the straightening block; The coefficient of friction between the NTC electrode and the DBC substrate under molten solder lubrication.

5. The semiconductor device packaging method according to claim 3, characterized in that: The spring stiffness of the compression spring satisfies the following condition: k≤F / ; Where k is the spring stiffness of the compression spring; F represents the destructive load of the NTC; This refers to the working compression of the spring.

6. The semiconductor device packaging method according to claim 1, characterized in that: The side of the corrective block is provided with a plurality of vent holes that penetrate the side wall of the corrective block, and the vent holes are connected to the cavity.

7. The semiconductor device packaging method according to claim 6, characterized in that: The vent is located at the top or upper side wall of the cavity of the corrective block.

8. The semiconductor device packaging method according to claim 1, characterized in that: The horizontal mounting arm is made of stainless steel or titanium alloy.

9. The semiconductor device packaging method according to claim 1, characterized in that: The corrective pressure block is made of alumina ceramic or aluminum nitride ceramic.

10. The semiconductor device packaging method according to claim 1, characterized in that: The top of the side wall of the base is provided with a rectangular groove; one end of the horizontal mounting arm is embedded in the rectangular groove and is detachably connected to the rectangular groove by a positioning pin.

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