Wafer Substrate & EPI

[Summary] Substrate is the basic material used to support and build other functional layers during semiconductor device manufacturing. The substrate can be divided into chemical substrates and physical substrates according to their manufacturing process and use. Common substrates are usually physical substrates, including single crystal silicon, gallium arsenide and silicon carbide.

The epitaxial layer (Epilayer) is a new layer of single crystals grown on a single crystal substrate that has been finely processed (cut, grinding, polishing, etc.). This new single crystal and the substrate can be of the same material or different materials. Almost all semiconductor devices are made on the epitaxial layer, so the electrical properties and reliability of the epitaxial layer will have a great impact on the device function.

Usually, the industry will use CAFM/SMM/SSRM to comprehensively evaluate the electrical performance of the substrate and epitaxial layer.