Electro-static discharge protection circuit and method for fabricating the same

An ESD protection circuit, comprising:

• a substrate;
• a well formed in the substrate;
• a drift region formed inside the well;
• a plurality of first diffusion layers respectively formed in the well and the drift region;
• a plurality of second diffusion layers respectively formed in the well and the drift region, wherein corresponding first and second diffusion layers in the well are formed separately from each other and those in the drift region are formed adjacent to each other;
• a source region formed in a manner of surrounding a second diffusion layer inside the well;
• and
• a gate electrode formed on the well between the source region and the drift region.

A method for fabricating an ESD protection circuit, comprising:

• providing a substrate in which a well, a device isolation layer and a diffusion barrier region are formed;
• forming a source region contacted with one sidewall of the diffusion barrier region and that of the device isolation layer;
• forming a drift region having a predetermined portion overlapped with the well;
• forming a gate electrode on the well between the source region and the drift region;
• forming two first diffusion layers inside the well and the drift region respectively;
• and
• forming two second diffusion layers respectively formed in the well and the drift region, wherein each of the second diffusion layers in the well is formed separately from a corresponding one of the first diffusion layers in the well through the device isolation layer and each of the second diffusion layers is formed adjacent to a corresponding one of the first diffusion layers in the drift region.