Patent ID: 7915638
Filing Date: 2011-03-29
Classification: H01L

Abstract:
1. A symmetric bidirectional silicon-controlled rectifier comprising: a substrate of a second conduction type; a first buried layer of a first conduction type and formed on said substrate; a first well and a second well both of said second conduction type and formed on said first buried layer; a middle region of said first conduction type and formed in between said first well and said second well; a first semiconductor area and a second semiconductor area both formed inside said first well; a third semiconductor area formed in a junction between said first well and said middle region, wherein a first gate is formed over a region between said second semiconductor area and said third semiconductor area; a fourth semiconductor area and a fifth semiconductor area both formed inside said second well; and a sixth semiconductor area formed in a junction between said second well and said middle region, wherein a second gate is formed over a region between said fifth semiconductor area and said sixth semiconductor area.