A method for improving the breakdown resistance of devices using BCB resin

Abstract

This invention proposes a method for improving the breakdown resistance of semiconductor devices using BCB resin. The method involves assembling semiconductor devices into a housing through processes such as arrangement, sintering, and bonding. BCB resin is then coated onto the uncapped housing using a suspension coating method, with the rotation speed gradually increasing from low to high to ensure uniform distribution of BCB within the housing. The housing is then placed in an oven with a protective gas atmosphere for step-temperature curing of the BCB. Finally, the housing is removed from the oven for encapsulation. This invention utilizes a suspension coating method to fill the housing with BCB resin, leveraging its high fluidity, thermal stability, and excellent mechanical and dielectric properties to ensure uniform coverage and surface flatness of the BCB resin within the housing, preventing bubble formation. The step-temperature curing process after filling ensures the thermal stability of the BCB resin, ultimately resulting in a device with high breakdown resistance after encapsulation.

Description

Technical Field

[0001] This invention relates to a method for improving the breakdown resistance of devices using BCB resin, belonging to the field of semiconductor device technology. Background Technology

[0002] Benzocyclobutene (BCB) thermosetting resin has excellent properties such as low dielectric constant, low water absorption, low high-frequency dielectric loss, and low curing temperature. Due to its excellent thermal, mechanical, and dielectric properties, it has gradually become a new generation of high-performance electronic materials and is applied in the field of high-end microelectronics.

[0003] When semiconductor devices are arranged, sintered, and bonded within a package, performance and reliability must be comprehensively considered. Especially under high voltage and high power conditions, air breakdown can easily occur between devices and between devices and the package, leading to burn-out. Therefore, to improve the breakdown characteristics between devices and between devices and the package, a high-dielectric-constant dielectric can be filled into the package. Existing methods typically use polyimide to fill the package; however, in practical applications, due to the limited filling capacity on the device surface and in the gaps between devices, polyimide cannot provide uniform coverage, and air bubbles are easily generated during the filling process. During high-temperature curing, this can easily form a porous cured layer, failing to effectively prevent breakdown. Summary of the Invention

[0004] The purpose of this invention is to solve the above-mentioned problems in the existing semiconductor device breakdown protection process, and to propose a method for improving the breakdown resistance of devices using BCB resin.

[0005] The technical solution of this invention: A method for improving the breakdown resistance of devices using BCB resin, specifically including the following steps:

[0006] 1) Assemble semiconductor devices in an uncapped housing through arrangement, sintering, and bonding processes. The semiconductor devices may be one or more of the following: silicon devices, gallium arsenide devices, gallium nitride devices, silicon carbide devices, indium phosphide devices, and gallium oxide devices.

[0007] 2) Apply BCB resin to the uncapped tube using a suspension coating method. Gradually increase the rotation speed from low to high speed. The suspension coating rotation speed and time are as follows: 50 rad / min, 15 seconds; 100 rad / min, 10 seconds; 300 rad / min, 7 seconds; 500 rad / min, 5 seconds. Ensure that the BCB resin is evenly and evenly distributed inside the tube, with no air bubbles in the filled area. The height of the filled BCB resin surface should be higher than the highest point of the device and bonding wire inside the tube, but not exceed the height of the tube wall.

[0008] 3) Place the tube shell in an oven with a protective gas atmosphere and let it stand for 6 hours. The protective gas in the oven is nitrogen. Under stable nitrogen pressure in the oven, the oxygen content is less than 100 ppm.

[0009] 4) In a protective gas atmosphere, BCB resin is cured in an oven using a stepped temperature treatment. The curing temperature and time settings are as follows: from room temperature, the temperature is increased to 40℃~60℃ after 1 hour and maintained at this temperature for 6 hours; after 1 hour, the temperature is increased to 90℃~110℃ and maintained at this temperature for 4 hours; after 2 hours, the temperature is increased to 140℃~160℃ and maintained at this temperature for 2 hours; after 2 hours, the temperature is increased to 190℃~210℃ and maintained at this temperature for 1.5 hours; after 1.5 hours, the temperature is increased to 240℃~260℃ and maintained at this temperature for 1 hour; and after 2 hours, the temperature is reduced to room temperature.

[0010] 5) Remove the tube shell from the oven and seal it.

[0011] Compared with the prior art, the advantages of the present invention are as follows: BCB resin is filled into the tube shell by suspension coating, which utilizes its high fluidity, thermal stability, and excellent mechanical and dielectric properties to ensure the uniformity of BCB resin coverage and surface flatness in the tube shell and avoid the generation of air bubbles. After the filled BCB resin is subjected to a step-curing process, the thermal stability of BCB resin is ensured. Finally, after encapsulation, a device with high breakdown resistance is formed. Attached Figure Description

[0012] Appendix Figure 1 ~Appendix Figure 2 This is a schematic diagram of the method for improving the breakdown resistance of devices using BCB resin proposed in this invention.

[0013] In the diagram, 1 is the tube shell, 2 is the device, 3 is the bonding wire, and 4 is BCB resin. Detailed Implementation

[0014] The technical solution of the present invention will be further described below with reference to the accompanying drawings. Examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0015] To simplify the disclosure of this invention, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0016] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structural material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structural materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0017] like Figures 1-2 As shown in this embodiment, a method for improving the breakdown resistance of a device using BCB resin is presented. The specific operation steps are as follows:

[0018] 1) Assemble the various semiconductor devices 2 inside the housing 1 as required, including the arrangement and sintering of the devices 2, the installation of the bonding wires 3, etc. The housing 1 is not sealed.

[0019] 2) BCB resin 4 is coated inside the uncapped tube shell 1 using a suspension coating method. The suspension coating rate and time are gradually increased from low speed to high speed, namely 50 rad / min for 15 seconds, 100 rad / min for 10 seconds, 300 rad / min for 7 seconds, and 500 rad / min for 5 seconds. The BCB resin 4 is evenly and flatly distributed inside the tube shell 1, with no air bubbles in the filling area. The height of the filled BCB resin 4 surface should be higher than the highest point of the device 2 and bonding wire 3 inside the tube shell 1, but not exceed the height of the tube shell 1 wall, leaving a margin for capping.

[0020] 3) Place tube shell 1 in an oven with a protective gas atmosphere and let it stand for 6 hours. The protective gas is nitrogen. Under stable nitrogen pressure in the oven, the oxygen content is less than 100 ppm.

[0021] 4) In a protective gas atmosphere, BCB resin 4 is cured in an oven using a temperature-step curing process. The curing temperature and time are set as follows: from room temperature, the temperature is increased to 50°C after 1 hour and maintained at this temperature for 6 hours; after 1 hour, the temperature is increased to 100°C and maintained at this temperature for 4 hours; after 2 hours, the temperature is increased to 150°C and maintained at this temperature for 2 hours; after 2 hours, the temperature is increased to 200°C and maintained at this temperature for 1.5 hours; after 1.5 hours, the temperature is increased to 250°C and maintained at this temperature for 1 hour; and after 2 hours, the temperature is reduced to room temperature.

[0022] 5) Remove the tube shell 1 from the oven and seal it.

[0023] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for improving the breakdown resistance of a device with a BCB resin, characterized by, The method specifically comprises the following steps: 1) assembling semiconductor devices in an unsealed tube shell through arrangement, sintering and bonding processes; 2) coating BCB resin in the unsealed tube shell by suspension coating, gradually increasing the rotation rate from low to high, so that the BCB resin is uniformly and flatly distributed in the tube shell; 3) placing the tube shell in an oven with a protective gas atmosphere and standing; 4) using the oven to perform temperature stepwise curing treatment on the BCB resin in the protective gas atmosphere; 5) taking the tube shell out of the oven and performing packaging treatment; The rotation rate and time of the suspension coating in the step 2) are 50 rad / min for 15 seconds, 100 rad / min for 10 seconds, 300 rad / min for 7 seconds and 500 rad / min for 5 seconds in sequence; The BCB resin filling area in the step 2) is free of bubbles, and the surface height of the filled BCB resin is higher than the highest point of the devices and bonding wires in the tube shell, but does not exceed the height of the tube shell wall; The curing temperature and time setting of the temperature stepwise curing treatment in the step 4) are as follows: 1) increasing the temperature from room temperature to 40-60℃ for 1 hour, maintaining the temperature for 6 hours; 2) increasing the temperature to 90-110℃ for 1 hour, maintaining the temperature for 4 hours; 3) increasing the temperature to 140-160℃ for 2 hours, maintaining the temperature for 2 hours; 4) increasing the temperature to 190-210℃ for 2 hours, maintaining the temperature for 1.5 hours; 5) increasing the temperature to 240-260℃ for 1.5 hours, maintaining the temperature for 1 hour; 6) decreasing the temperature to room temperature for 2 hours.

2. The method of claim 1, wherein the BCB resin is used to improve the breakdown voltage of a device. The semiconductor devices in the step 1) are one or a combination of silicon devices, gallium arsenide devices, gallium nitride devices, silicon carbide devices, indium phosphide devices and gallium oxide devices.

3. The method of claim 1, wherein the BCB resin is used to improve the breakdown voltage of a device. The protective gas in the oven in the step 3) is nitrogen, and the oxygen content in the nitrogen in the oven is less than 100 ppm in a stable state.

4. The method of claim 1, wherein the BCB resin is used to improve the breakdown voltage of a device. The standing time in the step 3) is 6 hours.

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