14.4.1 Design Guidelines for 3.3V LV SAB MOSFET Device¶
When using LV MOSFET (NMOS/PMOS) for ESD protection devices, it shall be marked by ESD_MK mark layer. The following layout guidelines are recommended.
RULE NO. |
DESCRIPTION |
RULE |
LVESD.1 |
LV MOSFET used for ESD protection should be enclosured by ESD_MK, ESD_MK must enclose well pick-up implant |
0 |
LVESD.2* |
Poly Channel-length for each finger in multi-finger transistors must be same |
|
LVESD.3 (a) |
Min. channel length for each finger (Recommended) |
0.3 |
LVESD.3 (b) |
Max. channel length for each finger |
0.5 |
G.LVESD.4 (a)** |
Recommended finger width for each finger |
25 |
LVESD.4 (b) |
Min. finger width for each finger |
20 |
LVESD.4 (c) |
Max. finger width for each finger |
60 |
G.LVESD.5 (a)** |
Recommended number of fingers share one pick-up ring in multi-finger transistors. |
8 |
LVESD.5 (b) |
Max. number of fingers share one pick-up ring in multi-finger Transistors |
16 |
G.LVESD.6 (a)** |
Recommended total finger width |
200 |
LVESD.6 (b) |
Min. total finger width |
160 |
LVESD.6 (c) |
Max. total finger width |
720 |
LVESD.7 |
SAB should cover drain and source and overlap gate or cover drain only with rule LVESD.7(a) partly overlap poly gate |
|
LVESD.7 (a) |
Min/max SAB overlap Poly gate |
0.05 |
G.LVESD.8 (a)** |
Recommeded at least one or nearest drain contact to gate edge space (DCGS) |
2 |
LVESD.8 (b) |
Min. drain contact to gate edge space (DCGS) |
1 |
LVESD.8 (c) |
Max. of at least one or nearest drain contact to gate edge space (DCGS) |
4 |
G_LVESD.10 |
Recommended well tap COMP to active COMP space in channel length direction. |
2 |
LVESD.11 |
Source COMP must enclose by LVS_Source |
0 |
LVESD.12 |
LVS_Source must butt to Poly edge |
0 |
G.LVESD.13** |
Recommended at least one or nearest source contact to gate edge space (SCGS) when SAB cover drain-source over poly gate |
0.7 |
LVESD.13(a) |
Min. source contact to gate edge space (SCGS) when SAB cover drain-source over poly gate |
0.15 |
LVESD.13(b) |
Max. of at least one or nearest source contact to gate edge space (SCGS) when SAB cover drain-source over poly gate |
1 |
COLVESD.7 |
Recommended/max. salicided block edge to at least one or nearest contact (CA) |
0.22 |
COLVESD.7(a) |
Min. salicided block edge to contact (CA) |
0.15 |
