Indium sheets play a crucial role in semiconductor sealing processes, primarily used to enhance the thermal and electrical performance and reliability of devices. Indium is a silvery-white metal with excellent plasticity and a low melting point (approximately 156.6 degrees Celsius), making it particularly useful in semiconductor packaging. Here are the applications and processes of indium sheets in semiconductor packaging:
- Preparation of Indium Sheets: First, high-purity indium ingots are obtained through smelting and purification processes. These ingots are then rolled into thin sheets. This process requires precise control of the thickness and dimensions of the indium sheets to meet packaging requirements.
- Base Preparation: Before adding the indium sheets to the base, the base must be cleaned and leveled to ensure that the indium sheets adhere well and conduct heat efficiently.
- Adding Indium Sheets: The pretreated indium sheets are added to the base at predetermined positions, usually through a hot pressing method, which softens the indium sheets and makes them adhere closely to the base.
- Chip Installation: After the indium sheets are added, the chip is installed onto the indium sheets, typically also through hot pressing, to form good thermal contact.
- Post-processing: Finally, the chip is encapsulated and tested to ensure the performance and reliability of the device. In this process, indium sheets provide excellent electrical and thermal contact, reducing the thermal resistance of the device.
Indium sheets are mainly used in the field of semiconductor packaging and play a particularly important role in lead-free packaging technology. Lead-free packaging aims to reduce harm to the environment and human health. Due to its excellent electrical properties and plasticity, indium sheets are an ideal material for lead-free packaging. Using indium sheets in semiconductor device packaging can achieve lead-free soldering, avoiding environmental and health hazards while ensuring soldering reliability and stability.
Indium sheets have excellent thermal conductivity, making them widely used in the manufacturing of heat dissipation modules in semiconductor packaging. Semiconductor devices generate a significant amount of heat during operation, and the high thermal conductivity of indium sheets can effectively and quickly transfer heat to the heat dissipation modules, ensuring the device operates at a normal temperature. The softness and plasticity of indium sheets also make them easier to combine with other thermal dissipation materials to form heat dissipation modules.
In thermal applications, indium sheets are an excellent material mainly because of their high thermal conductivity (86 W/mK), which is far higher than common metals like copper and aluminum. This makes indium an ideal heat dissipation material for high-frequency, high-speed electronic devices, and high power density equipment. Indium sheets can be mechanically processed into different shapes and sizes to meet various thermal management needs. In addition to high thermal conductivity, indium also has good ductility, corrosion resistance, and thermal conductivity at low temperatures.