Silicon wafer annealing is a high-temperature furnace operation that can relieve stress in silicon, activate or move dopants, densify deposited or grown films, and repair implant damage in wafer processing. It can also change film to film or film to substrate interfaces for wafers with multiple films, bonded wafers and SOI applications.
Due to its wide range of uses, wafer annealing can take anywhere from a few minutes to more than a day. In rapid thermal processing/annealing (RTP/A) applications, the entire process is rarely longer than a few minutes, whereas to densify films or bond wafers, wafers can be in the furnace for more than a day.
Silicon Valley Microelectronics offers annealing solutions for wafers ranging in diameter from 25mm to 300mm. We provide many standard anneal recipes or can provide custom annealing to your specific requirements.
Most wafer annealing takes place in a three zone atmospheric pressure chemical vapor deposition (APCVD) furnace. First, the wafers are loaded into the furnace where they are arranged vertically or horizontally, depending on the furnace style. Next, the furnace heats to between 450°C and 1200°C depending on the application, and gas fills to the furnace to anneal the substrates. After the wafer anneal is complete, the wafers cool slowly to prevent cracking and surface damage.
SVM Wafer Annealing capabilities:
- Nitrogen annealing: Pure nitrogen gas flows through the chamber with the wafers. Once the chamber fills with nitrogen gas, the system is heated to ~1100°C – 1300°C for up to 4 hours. Using pure nitrogen prevents any unwanted oxide growth on the wafer surface during annealing.
- Forming gas annealing: This process is the same as nitrogen annealing. Instead of pure nitrogen, the forming gas anneal uses a mixture of between ~90% & 96% nitrogen and ~4% & 10% hydrogen. The gas gets this mixture by thermally cracking ammonia. Using ammonia allows for more precise control of hydrogen concentration within the forming gas.
Please CONTACT SVM today for further information on wafer annealing, to discuss your current requirements, or to request a quote. To view a portion of our multi-million dollar inventory, please visit our ONLINE INVENTORY.