Patent ID: 6274909
Filing Date: 2001-08-14
Classification: H01L,Y10S

Abstract:
An ESD (electrostatic discharge) device with protective guard rings, comprising:a) an ESD device on a P-substrate connected to a chip pad on surface of said P-substrate,b) said ESD device surrounded by and laterally separated from a P+ diffusion guard ring within said P-substrate, wherein said P+ diffusion guard ring starts at the surface of the P-substrate and extends vertically a first distance within the P-substrate,c) an N+ diffusion guard ring surrounding and laterally separated from said P+ diffusion guard ring,d) said N+ diffusion guard ring contained within an N-well surrounding and laterally separated from the region of said P+ diffusion guard ring, wherein said N+ diffusion guard ring starts at the surface of the P-substrate and extends vertically a second distance within the P-substrate,e) said N-well sifting on top of a deep N-well surrounding and laterally separated from said P+ diffusion guard ring on said P-substrate, wherein said deep N-well starts at said second distance within said P-substrate and extends vertically to a third distance further from the surface of said substrate than said second distance.