Patent ID: 7355250

Claim:
An electrostatic discharge (ESD) device with controllable holding current, comprising: a P-type substrate; an N-well, formed in said P-type substrate; a first N+ doped region, formed in said N-well; a first P+ doped region, formed in said N-well, wherein a first distance is kept between said first P+ doped region and said first N+ doped region; a second N+ doped region, formed between said first P+ doped region and a first field oxide; a third N+ doped region, formed inside said P-type substrate and outside said N-well, wherein said third N+ doped region is isolated from said N-well, and said third N+ doped region is isolated from said second N+ doped region by said first field oxide; a second P+ doped region, formed inside said P-type substrate and outside said N-well, wherein said second P+ doped region is isolated from said N-well, and a second distance is kept between said second P+ doped region and said third N+ doped region, and a holding current of the ESD device is determined by modulating said first distance and said second distance, wherein said first distance and said second distance are different one from another; a first electrode, electrically coupled to said first P+ doped region and said first N+ doped region via a first electric conductor; and a second electrode, electrically coupled to said third N+ doped region and said second P+ doped region via a second electric conductor.