Development of multi-state anti-fuse utilizing location of gate-oxide breakdown of MOSFET

Research Project

Project/Area Number	24760269
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Electron device/Electronic equipment
Research Institution	The University of Tokyo
Principal Investigator	HIROSHI Fuketa 東京大学, 生産技術研究所, 助教 (30587423)
Project Period (FY)	2012-04-01 – 2014-03-31
Project Status	Completed (Fiscal Year 2013)
Budget Amount *help	¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000) Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000) Fiscal Year 2012: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Keywords	ゲート酸化膜破壊 / 電子ヒューズ / OTP ROM / ROM
Research Abstract	Recently, a programmable read-only memory (OTP ROM) based on an anti-fuse using the gate-oxide of MOS transistor has been widely used for analog trimming, and a lager-capacity OTP ROM has been required. Therefore, this project developed a multi-state anti-fuse utilizing the location of gate-oxide breakdown of MOS transistor, which enables a lager-capacity OTP ROM. In order to realize such multi-state anti-fuse, the location of gate-oxide breakdown must be controllable. However, the method to control the location had not been revealed. In this project, the method to control the location was proposed and verified with silicon measurements for the first time. Then, OTP ROM with the developed multi-state anti-fuse was designed and fabricated in 0.18um CMOS process, and we confirmed that the area per bit of OTP ROM can be reduced compared with the conventional work by using the multi-state anti-fuse.