A stacked-NMOS triggered silicon-controlled rectifier (SNTSCR) is proposed as the electrostatic discharge (ESD) clamp device to protect the mixed-voltage I/O buffers of CMOS ICs. This SNTSCR device is fully compatible to general CMOS processes without using the thick gate oxide to overcome the gate-oxide reliability issue. ESD robustness of the proposed SNTSCR device with different layout parameters has been investigated in a 0.35-μm CMOS process. The HBM ESD level of the mixed-voltage I/O buffer with the stacked-NMOS channel width of 120 μm can be obviously improved from the original ∼ 2 kV to be greater than 8 kV by this SNTSCR device with a device dimension of only 60 μm/035 μm.
|Number of pages||3|
|Journal||IEEE Electron Device Letters|
|State||Published - 1 Jun 2002|
- Electrostatic discharge (ESD)
- ESD protection
- Mixed-voltage I/O buffer
- Silicon-controlled rectifier (SCR)