Patent ID: 6946690
Filing Date: 2005-09-20
Classification: H01L

Abstract:
1. A method of manufacturing a device having an elevated holding voltage, and formed in a semiconductor material of a first conductivity type, the semiconductor material having a dopant concentration, the device comprising a well of a second conductivity type formed in the semiconductor material, the well having a dopant concentration; a first region of the second conductivity type formed in the well, the first region having a dopant concentration greater than the dopant concentration of the well, the first region being connected to a first node; a second region of the first conductivity type formed in the well, the second region having a dopant concentration greater than the dopant concentration of the semiconductor material, the second region being connected to the first node; a third region of the second conductivity type formed in the semiconductor material, the third region having a dopant concentration greater than the dopant concentration of the well, the third region being connected to a second node; and a fourth region of the first conductivity type formed in the semiconductor material, the fourth region having a dopant concentration greater than the dopant concentration of the semiconductor material, and being connected to the second node, the method comprising; adjusting the size of the second region to limit injection of minority carriers to achieve the desired elevated holding voltage.