Attopsemi’s I-fuse™ OTP memory has the following advantages over the competitive technologies:
- Proven mechanism. Our I-fuse™ OTP memory is based on the irreversible mechanism of electro-migration that has been studied in academia and industry for more than 60 years. Other OTP technologies are based on breaking fuse, rupturing oxide, or storing charges. Those “non-volatile” programming means are explosive or statistical natures that can result in grow back or self-healed and lead to poor reliability.
- High reliability. Our I-fuse™ OTP memory is strictly based on electro-migration for reliable programming. The programming mechanism is deterministic, controllable, and can be modeled precisely by physical laws. Our I-fuse™ at Vanguard’s 0.16um high-voltage process passed High Temperature Storage (HTS) test at 300°C for 3,000 hours, which exceeds the condition F of 300°C for 1000 hrs in JESD22-A103C. Our I-fuse™ also exceeds the highest grade 0 of 175°C for 1,000 hrs in AEC-Q100C_Rev H automotive specifications.
- Small size. Our OTP cell size is only 1/100 of the conventional e-fuse cells in the comparable CMOS technologies by using 1R1D cell instead of 1R1T. The D means “diode”, which is a source/drain junction diode of a PMOS device available in any CMOS processes. The effective IP size is also about half to one-third of the other OTP technologies because of small cell size and low overhead peripheral circuits.
- High density. The achievable I-fuse™ density can be from a few bits to several megabits due to small cell size, high yield, high reliability OTP, and low overhead peripherals.
- Low voltages. Unlike other OTP technologies, the I-fuse™ OTP memory only uses the convenient core and I/O voltages for program and read, i.e. 1.8V/2.5V/3.3V, so that the I-fuse™ is very easy to use. No needs to have large area and power hungry charge pumps.
- Wide temperature range. Our I-fuse™ OTP memory has been qualified from -55°C to 300°C for over 1,000 hours. Moreover, our I-fuse™can pass High Temperature Storage (HTS) at 400°C for 8 hours with 0 defect in 3Mb. Other OTP technologies cannot even pass 400°C for 2 hours with 20-30 defects per 1Mb.
- Scalable. Our I-fuse™ OTP cell is very robust and can be scalable and shrinkable following Moore’s law.
- High yield. Since our programming method is deterministic, controllable, and can be modeled precisely by physical laws, our program yield can be guaranteed 100%, if meeting our programming specifications. If there is any yield loss, it would be due to pre-program fab defects. In the past 4 years, we only saw less than 10 defects out of total of 1.1 billion I-fuses™ accumulated from more than 40 silicon shuttles from 0.5um to 28nm CMOS.