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

Image Number 9 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
Wall flow type exhaust gas purification filter
Novelty snacks and method of manufacture of same
Method and apparatus for visual neural stimulation
Method to prevent hyper frame number de-synchronization in a wireless communication system
Editing device and editing method
Resist underlayer film forming composition for lithography, containing aromatic fused ring-containing resin
Electronic system auto-mute control circuit and control method thereof
  Randomly Featured Patents
Cooking utensil for uniform heating in microwave oven
Angular implant device
Enzymatic reagent inks for use in test strips having a predetermined calibration code
Comparator array logic
Communication system, communication method, video output apparatus and video input apparatus
Composite glass and resin optical element with an aspheric surface
Polymer having polycyclic groups and coating compositions thereof
Apparatus for treating a gas stream
Insect collection apparatus
Multiplex communication system using separated and multiplexed data