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
Semiconductor pressure sensor
Mold for nanoimprinting, its production process, and processes for producing molded resin having fine concavo-convex structure on its surface and wire-grid polarizer
Intake parameter-calculating device for internal combustion engine and method of calculating intake parameter
Cosmetic or pharmaceutical peptides containing uncoded amino acids and their use in the treatment and/or care of the skin, mucous membranes, or scalp
Signal conversion control circuit for touch screen and method thereof
Methods and apparatus for performing multiple photoresist layer development and etching processes
Scalable pixel coverage function-map
  Randomly Featured Patents
LED traffic signal and optical element therefor
Process for hardening microcapsules
Multi-outlet power strip
Integrated circuit package resistance measurement
Use of aminoglycosides to protect against excitotoxic neuron damage
Graph-based pattern matching in L3GO designs
Combined back support and neck support pillow of synthetic foam
Three-way actuation control of a hydraulically actuated fuel injector
High softening point synthetic resin
Bone fixation assembly and method