1、 Range and stability of thermal conductivity
Thermal conductive silicone sheets have a high selectivity in terms of thermal conductivity, ranging from 0.8 w/k · m to 3.0 w/k · m or higher, and have stable performance and reliable long-term use Currently, the highest thermal conductivity of double-sided adhesive tape does not exceed 1.0w/k-m, and the thermal conductivity effect is not ideal; Thermal conductive silicone grease belongs to the room temperature curing process, which is prone to surface cracking, unstable performance, easy volatilization and flow at high temperatures. Its thermal conductivity will gradually decrease, which is not conducive to long-term reliable system operation.
2、 Bridge the process gap in structure and reduce the process gap requirements for radiators and heat dissipation structural components
The thickness and hardness of the thermal conductive silicone sheet can be adjusted according to different designs. Therefore, it can bridge the size difference of the heat dissipation structure, chip, etc. in the thermal conductive channel, reduce the requirement for the contact surface of the heat sink in the structural design, especially for flatness and roughness. If the processing accuracy is improved, it will greatly increase the product cost. Therefore, the thermal conductive silicone sheet can fully increase the contact area between the heat source and the heat dissipation device, reducing the production cost of the heat sink. In addition to the traditional PC industry, the new heat dissipation solution now is to remove the traditional heat sink and unify the structural components and heat sink into a heat dissipation structural component. In PCB layout, heat dissipation chips are placed on the back side, or when placing them on the front side, heat dissipation holes are opened around the chips that need to be dissipated. Heat is conducted to the back of the PCB through copper foil or other materials, and then filled with thermal conductive silicon film to establish thermal conductive channels that lead to the heat dissipation structural components (metal brackets, metal shells) below or on the side of the PCB. This optimizes the overall heat dissipation structure and reduces the cost of the entire heat dissipation solution.
3、 EMC, insulation performance
Thermal conductive silicone sheets, due to their inherent material properties of insulation and thermal conductivity, have good protection against EMC. Due to the silicone material, they are not easily pierced or torn or damaged under pressure, making EMC reliability relatively good. Due to the limitations of its material properties, thermal conductive double-sided tape has relatively low EMC protection performance and often cannot meet customer requirements. It is limited in use and can only be used when the chip itself has been insulated or the chip surface has been EMC protected. Thermal conductive silicone grease has relatively low EMC protection performance due to its material characteristics, and often cannot meet customer requirements. Its use is limited, and generally only the chip itself can be insulated or the chip surface can be EMC protected before use.
4、 The effect of shock absorption and sound absorption
The silicone carrier of thermal conductive silicone film determines its excellent elasticity and compression ratio, resulting in good shock absorption effect. Adjusting the density and hardness can also produce good absorption of low-frequency electromagnetic noise. The bonding method of thermal conductive double-sided tape determines that it does not have shock-absorbing and sound-absorbing effects. The use of thermal conductive silicone grease in hard contact determines that it does not have shock-absorbing and sound-absorbing effects.
5、 The convenience of installation, testing, and reusability
Thermal conductive silicone sheet is a stable solid, with optional adhesive strength and easy disassembly; Has elastic recovery and can be reused. Once used, the thermal conductive double-sided tape is not easy to disassemble and poses a risk of damaging the chip and surrounding components, making it difficult to completely disassemble. When thoroughly scraped, it will scratch the surface of the chip and bring interference factors such as dust and oil stains when wiping, which is not conducive to thermal conductivity and reliable protection. Thermal conductive silicone grease cannot be disassembled and must be carefully wiped. It is not easy to wipe thoroughly, especially when replacing the thermal conductive medium for testing, which will affect the reliability of the test data and thus affect the engineer's judgment.
