4-inch Fe-doped InP substrates manufactured using vertical boat technique

Recent progress of high speed optical communication systems have been increasing the fabrication scale of devices, such as HBTs and OEICs. These devices will require semi-insulating Fe-doped InP substrates that are larger in diameter (4-inch) and higher in quality to improve device performance and reduce costs. With the growth of larger diameter InP crystals the increase of dislocation densities becomes critical. Though a boat growth method is the most appropriate for achieving low dislocation density, the boat growth of InP is difficult because of twinning issues. Therefore, most previous efforts have adopted a < 111 >-orientation to prevent twinning. However, this type of orientation is not suitable for the production of [100] substrates. SEI has succeeded in developing 4-inch Fe-doped InP substrates that are higher in quality using our VB (Vertical Boat) technique.