The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 31, 1991
Filed:
Jul. 26, 1990
Daniel Quessada, Pourrieres, FR;
SGS-Thomson Microelectronics S.A., Gentilly, FR;
Abstract
An integrated circuit includes a vertical power transistor, a depletion-mode lateral MOS logic transistor and a lateral Schottky diode in an N.sup.+ epitaxial semiconductor layer of an N substrate. The depletion-mode lateral transistor and Schottky diode are in a P well formed in the epitaxial layer during a first doping step. The vertical power transistor and depletion-mode lateral transistor include P.sup.+ semiconductor regions formed during a second doping step. The lateral transistor and Schottky diode include an N doped semiconductor channel layer formed during a third doping step so they have similar characteristics. The vertical power transistor includes a P doped semiconductor channel layer formed during a fourth doping step. The lateral transistor, Schottky diode and channel of the vertical power transistor include N.sup.30 doped semiconductor regions formed during a fifth doping step. The semiconductor region formed during the fifth step associated with the Schottky diode forms a ring around the layer of the diode formed during the third step. Metal electrodes are formed on regions of the transistors and diode as formed during the fifth step and on the diode layer formed during the third step and on regions formed during the second step. The layer formed during the third step forms a junction about 0.7.mu. below the substrate and has a surface dopant concentration of about 10.sup.16 atoms/cm.sup.3.