EP0436038A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor device and method of producing the same
Assignee: Seiko Instruments Inc
•
Filing: 1990-07-11
•
Granted: —
•
Expires: 2010-07-11
Abstract
Abstract An insulated gate field-effect transistor used as a switching element in computers and a method of producing the same. In order to improve dynamic characteristics of the transistor by decreasing the junction capacitance between a substrate (1) and a source (7) or a drain (8), an an insulating layer (2) is provided under the source region and the drain region. In order to decrease the drop of carrier mobility and to suppress the short channel effect, furthermore, the impurity concentration is lowered on the surface of the semiconductor layer just under the gate and is heightened on the side of the substrate.
Inventors
- 👤 Kenji Seiko Instruments Inc. Aoki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 00:38
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/027; H10D30/0278; H10D30/60; H10D62/00; H10D62/10; H10D62/113; H10D62/115; H10D62/116; H10D62/17; H10D62/213; H10D62/221; H10D62/235; H10D62/314; H10D62/351; H10D62/357; H10D62/364; H10D62/371; H10P; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1908; H10W; H10W10/00; H10W10/10; H10W10/181
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
58 words
A semiconductor device in which a gate is formed on the portion between source and drain regions through an insulating film and in which a semiconductor layer just below the gate has a conductivity type opposite to that of the source and drain regions, characterized in that an insulating film is formed below the source and drain regions.
Claim 2
Dependent Claim
24 words
A semiconductor device according to claim 1, wherein the insulating film layer below the source and drain regions is made of SiO₂ or SiN.
Claim 3
Dependent Claim
30 words
A semiconductor device according to claim 1,wherein the impurity concentration of the semiconductor layer in the vicinity of the surface is low and that of the bulk side is high.
Claim 4
Dependent Claim
20 words
A semiconductor device according to claim 3, wherein the semiconductor layer just below the gate comprises plural epitaxially grown layers.
Claim 5
Dependent Claim
30 words
A semiconductor device according to claim 3, wherein the layer in the vicinity of the surface of the semiconductor layer having low impurity concentration is thinner than a depletion layer.
Claim 6
Dependent Claim
31 words
A semiconductor device according to claim 3, wherein the thickness of the layer in the vicinity of the surface of the semiconductor layer having low concentration is 200 - 800 Å.
Claim 7
Independent Claim
112 words
A method for making a semiconductor device comprising; a first step of forming an insulating film on, at least, a part of a surface of a first conductivity type semiconductor region a second step of providing a semiconductor layer of the same conductivity type as the first conductivity type on the seimconductor region including the insulating film, and a third step of forming a source and a drain of a second conductivity type different from the first conductivity type by an ion implantation after having formed a gate electrode on the semiconductor layer through a gate insulating film, wherein at least the insulating film is provided below the source and the drain.
Claim 8
Dependent Claim
42 words
A method for making a semiconductor device acccording to claim 7, wherein the second step of providing the first conductivity semiconductor layer is a step to carry out a lateral epitaxial growth seeding the exposed region of the surface of the semiconductor.
Claim 9
Dependent Claim
35 words
A method for making a semiconductor device according to claim 7, wherein an impurity concentration of the semiconductor layer formed at the second step increases in proportion to a distanc from the gate insulating film.
Claim 10
Dependent Claim
38 words
A method for making a semiconductor device according to claim 8 or 9, wherein the molecular layer epitaxial growth method or the molecular beam epitaxial growth method is used at the second step of forming the semiconductor layer.
Claim 11
Independent Claim
107 words
A method for making a semiconductor comprising; a first step of forming a gate insulating film on a first conductivity type semiconductor substrate and a gate electrode through the gate insulating film, a second step of forming an oxide film below the regions of the semiconductor substrate, where a source and a drain are to be formed by an implantation of oxygen ions while leaving a resist on the gate electrode formed at the first step, and a third step of forming the source and the drain of a second conductivity type by introducing impurity atoms of the second conductivity type different from the first conductivity type.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.