Resources Contact Us Home
Manufacturing method of well region in coms intergrated circuit

Image Number 7 for United States Patent #5114868.

First, N-type channel stoppers are formed in an element formation region of a P-channel MOS transistor and in an element isolation region of the P-channel MOS transistor, of a CMOS transistor. After forming a field oxide film, an N well is formed in the element formation region of the P-channel MOS transistor. In spite of the fact that the dose of ions used for the formation of an N-type channel stopper is smaller than the dose of ions used for the formation of an N well, the surface concentration of the N-type impurity of the N-type channel stopper is higher than that of the N well. The N-type impurity concentration in the portion where the N-type channel stopper and the N well are brought into contact, becomes uniform. The variability in the threshold voltage of the P-channel MOS transistor, the threshold voltage of the P-channel parasitic MOS transistor, the junction breakdown voltage of the P.sup.+ diffused layer and the junction capacitance of the P.sup.+ diffused layer is reduced, so that the device obtained is suited for the submicron process.

  Recently Added Patents
System and method for locating, tracking, and/or monitoring the status of personnel and/or assets both indoors and outdoors
Method, system and computer program product for managing funds in custodial deposit accounts
Suspension with flexure having laminated structure and bonding pads on opposing surfaces thereof, and head gimbal assembly and disk drive unit with the same
Magnetic impedance element and magnetic sensor using the same
Opportunistic modem
Data unit receiver and sender control method
Method and apparatus for controllable communication
  Randomly Featured Patents
Microprocessor controlled ambulatory medical apparatus with hand held communication device
Parking assist system
Novel indole carboxamides
Apparatus and method for single or multiple temperature zone(s) in refrigerated vending machine
Early estimation of power consumption for electronic circuit designs
Hand stabilizing identification member for an instrument panel
Method of forming a fine pattern
Safety spectacles with brow protector
Auto-aligning ablating device and method of use
Electromagnetic clutch