One-time programmable memory using fuse/anti-fuse and vertically oriented fuse unit memory cells
US6584029B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 2001 |
| Grant date | Jun 24, 2003 |
| Priority date | — |
| Expiry date | Aug 9, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A one-time programmable (“OTP”) memory includes one or more memory arrays stacked on top of each other. The OTP memory array is a cross-point array where unit memory cells are formed at the cross-points. The unit memory cell may include a fuse and an anti-fuse in series with each other or may include a vertically oriented fuse. Programming the memory may include the steps of selecting unit memory cells, applying a writing voltage such that critical voltage drop across the selected cells occur. This causes the anti-fuse of the cell to break down to a low resistance. The low resistance of the anti-fuse causes a high current pulse to be delivered to the fuse, which in turn melts the fuse to an open state. Reading the memory may include the steps of selecting unit memory cells for reading, applying a reading voltage to the selected memory cells and measuring whether current is present or not. Equipotential sensing may be used to read the memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.