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
Handheld electronic device with text disambiguation employing advanced editing feature
Spatially pre-processed target-to-jammer ratio weighted filter and method thereof
Matching a usage history to a new cloud
Bisphosphonate compounds
For a given cell in a spreadsheet, evaluating an unlimited number of conditional formatting rules and applying multiple corresponding formats to the cell
Manipulation of an alternative respiratory pathway in photo-autotrophs
Semiconductor device and method of manufacturing the same
  Randomly Featured Patents
Sealed non-separable combined bearing
Method and apparatus for association of a radio frequency identification tag with digital data for distribution
Process of making oriented films of conductive polymers
Method of manufacturing flash memory device
Shaft mounted valve position sensor
Financing party payment for calls with a wireless subscriber
Bowling ball handling apparatus
System and method for plasma etch on a spherical shaped device
Display apparatus containing controller driver with correcting circuit and method of driving display panel
Antihypertensive tricyclic azepine derivatives useful as inhibitors of enkephalinase and ACE