7μm Pitch deep trench super junction process development

With the rapid development of Super-junction(SJ) process in MOSFET, it is more and more widely used in power switcher area, and the performance of on resistance and switch speed became lower and faster[1]. The structure becomes more and more compacted. The pitch of SJ structure is becoming more and more narrow to fit the developing trend, thus more gross dies can be got and the cost will be reduced. HuaHong Grace(HHGRACE) has developed its own deep trench SJ MOSFET platform, and has optimized the process to make the platform keeping up with the technology developing trend. For the SJ MOSFET platform, it has gone through 3 periods: Generation L0(16μm pitch@RSP 24mohm·cm²), 2.0(11pm pitch@RSP 18mohm·cm²) and 3.0(9μm pitch@RSP 11mohm·cm²). Now HHGRACE is developing the 7μm pitch SJ process technology, and it can get RSP 10mohm·cm² now. This paper describes the deep trench SJ developing history and new direction, also the achievements during the process optimization for 7μm pitch deep trench SJ structure.