Wafer thinning, also known as backgrinding, is a semiconductor fabrication process that reduces the thickness of a wafer to enable high-density packaging and stacking of integrated circuits, crucial for compact electronic devices. SMEC (Samsung Machine Tool Engineering Company) and Chevalier have booth adapted their CNC's to perform this application.
Here's a more detailed explanation:
Purpose:
Wafer thinning is essential for creating extremely thin wafers, which are needed for high-density packaging and stacked configurations in small-scale electronic devices.
Process:
The process involves removing material from the backside of the wafer to achieve a specific thickness.
Methods:
- CNC Grinding: With the use of CNC's adapted for grinding applications, mechanical grinding is the most common method involves mechanically grinding the backside of the wafer to achieve the desired thickness, often using a two-step process of coarse and fine grinding.
- Chemical-Mechanical Planarization (CMP): CMP is another method used for wafer thinning, which involves using a slurry and a polishing pad to remove material from the wafer surface.
- Wet Etching: Liquid etchants are used to dissolve and remove material from the wafer surface.
- Dry Etching: Plasma etching can also be used to remove material from the wafer surface.
- Benefits:
- Improved Chip Size Specifications: Thinning allows for smaller and more compact devices.
- Better Heat Dissipation: Thinner wafers can dissipate heat more effectively.
- Meets Packaging Process Requirements: Wafer thinning is crucial for achieving the desired packaging configurations.
- Enables High-Density Packaging: Thin wafers allow for more components to be packed into a smaller space.
- Improved Manufacturability: Thinner wafers can lead to reduced wafer warpage/stress, better lithographic resolution, lower wafer breakage rates, and higher die yields per wafer.
- Examples of Applications:
Smartphones, USB memory sticks, handheld music players, and microchips.
- Ultra-thin wafers:
Wafer thinning is crucial for producing the extremely thin chips needed for cutting-edge applications.