Patent EP0268472A2 successfully refreshed from Google Patents.
EP0268472A2
Expired / Lapsed
EP
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Step-cut insulated gate static induction transistors and method of manufacturing the same
Assignee: Japan Science and Technology Agency
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Filing: 1987-11-18
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Granted: —
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Expires: 2007-11-18
Abstract
Abstract A step-cut insulated gate static induction transistor can accurately make a channel length and a gate length and is excellent as a high speed transistor but is greatly: affected by a deviation in mask alignment in the manufacturing process. This invention utilizes the fact that a gate portion formed in a previous processes is used as a mask in a post portion to thereby self-adjustably form the post portion, thus eliminating the influence of the deveation in mask alignment. In addition, a construction has been invented in which a current flowing through a protion apart from a gate between a drain and a source can be restricted. The aforesaid manufacturing method is also used for this improved construction.
Inventors
- 👤 Junichi Nishizawa
- 👤 Nobuo Aramoto-Apartment Takeda
- 👤 Soubei Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 22:29
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/012; H10D30/202; H10D62/00; H10D62/10; H10D62/17; H10D62/213; H10D62/221; H10D62/228; H10D84/00; H10D84/80; H10D84/82; H10P; H10P14/00; H10P14/60; H10P14/61; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/069
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
64 words
A method of manufacturing an step-cut insulated gate static induction transistor including the processes of anisotropic etching for forming a U-shaped groove in a main surface of a semiconductor substrate, forming a gate oxide film on a side wall of said U-shaped groove, and forming a region acting as a drain or a source, at least one of said processes being self-adjustably carried out.
Claim 2
Independent Claim
64 words
A method of manufacturing an step-cut insulated gate static induction transistor including the processes of anisotropic etching for forming a U-shaped groove in a main surface of a semiconductor substrate, forming a gate oxide film on a side wall of said U-shaped groove, and forming a region acting as a drain or a source, at least one of said processes being self-adjustably carried out.
Claim 3
Independent Claim
62 words
A method of manufacturing an step-cut insulated gate static induction transistor comprising the processes of anisotropic etching for forming a U-shaped groove in a main surface of a semiconductor substrate, selective oxidation while self-adjustably leaving mask material selective oxidation only on a side wall of said U-shaped groove, and forming a gate oxide film in a window formed by said selective oxidation.
Claim 4
Independent Claim
62 words
A method of manufacturing an step-cut insulated gate static induction transistor comprising the processes of anisotropic etching for forming a U-shaped groove in a main surface of a semiconductor substrate, selective oxidation while self-adjustably leaving mask material selective oxidation only on a side wall of said U-shaped groove, and forming a gate oxide film in a window formed by said selective oxidation.
Claim 5
Dependent Claim
70 words
A method of manufacturing an step-cut insulated gate, static induction transistor according to Claim 2 wherein said method includes the processes of using a silicon nitride film as said mask material for selective oxidation, self-adjustably leaving a polycrystalline silicon film deposited on said silicon nitride film on the side wall of said U-shaped grrove by anisotropic etching, and using the same as a mask to pattern said silicon nitride film.
Claim 6
Dependent Claim
36 words
A method of manufacturing a step-cut insulated gate static induction transistor according to Claim 2 wherein a number of step-cut insulated gate static induction transistors are integrated and formed on the semiconductor substrate by said method.
Claim 7
Independent Claim
67 words
A method of manufacturing a step-cut insulated gate static induction transistor comprising the processes of anisotropic etching for forming an U-shaped groove in a main surface of a semiconductor substrate, forming a gate oxide film, self-adjustably leaving a gate electrode only on the side wall of said U-shaped groove, and using said gate electrode as a mask to self-adjustably form a drain region and a source region.
Claim 8
Independent Claim
67 words
A method of manufacturing a step-cut insulated gate static induction transistor comprising the processes of anisotropic etching for forming an U-shaped groove in a main surface of a semiconductor substrate, forming a gate oxide film, self-adjustably leaving a gate electrode only on the side wall of said U-shaped groove, and using said gate electrode as a mask to self-adjustably form a drain region and a source region.
Claim 9
Dependent Claim
47 words
A method of manufacturing a step-cut insulated gate static induction transistor according to Claim 5 including the step of using a polycrystalline silicon as said gate electrode material to self-adjustably form said polycrystalline silicon on the side wall of said U-shaped groove by PCl₃ anisotropic plasma etching.
Claim 10
Dependent Claim
41 words
A method of manufacturing an integrated circuit of the step-cut insulated gate static induction transistor as defined in Claim 5. wherein a number of step-cut insulated gate static induction transistors are integrated and formed on the semiconductor substrate by said method.
Claim 11
Independent Claim
71 words
A method of manufacturing a step-cut insulated gate static induction transistor comprising the processes of anisotropic etching for forming a U-shaped groove in a main surface of a semiconductor substrate, forming a layer constituting a first channel, selective oxidation while self-adjustably leaving a mask material for selective oxidation only on the side wall of said U-shaped groove, and forming a gate oxide film in a window formed by said selective oxidation.
Claim 12
Independent Claim
71 words
A method of manufacturing a step-cut insulated gate static induction transistor comprising the processes of anisotropic etching for forming a U-shaped groove in a main surface of a semiconductor substrate, forming a layer constituting a first channel, selective oxidation while self-adjustably leaving a mask material for selective oxidation only on the side wall of said U-shaped groove, and forming a gate oxide film in a window formed by said selective oxidation.
Claim 13
Dependent Claim
99 words
A step-cut insulated gate static induction transistor comprising a U-shaped groove in a main surface of a semiconductor substrate and a drain region having a high impurity concentration provided on the top of said U-shaped groove, and a source region having a high impurity concentration provided along the bottom of said U-shaped groove so as not to provide a portion opposed to said drain region, characterized in that a current flowing through a channel region between said drain region and said source region is controlled by an insulated gate provided on at least a part of said U-shaped groove.
Claim 14
Dependent Claim
99 words
A step-cut insulated gate static induction transistor comprising a U-shaped groove in a main surface of a semiconductor substrate and a drain region having a high impurity concentration provided on the top of said U-shaped groove, and a source region having a high impurity concentration provided along the bottom of said U-shaped groove so as not to provide a portion opposed to said drain region, characterized in that a current flowing through a channel region between said drain region and said source region is controlled by an insulated gate provided on at least a part of said U-shaped groove.
Claim 15
Dependent Claim
47 words
A step-cut insulated gate static induction transistor according to Claim 9 wherein a high impurity concentration region having different conductiveity type of said drain region and said source region is provided in the vicinity of said source region to thereby restrict a region through which current flows.
Claim 16
Dependent Claim
23 words
A step-cut insulated gate static induction transistor according to Claim 9 or 10 wherein the drain region is exchanged with the source region.
Claim 17
Dependent Claim
30 words
A step-cut insulated gate static induction transistor according to any of Claims 9 to 11 wherein said transistor comprises at least one of constituent elements of the semiconductor integrated circuit.
Claim 18
Dependent Claim
178 words
A step-cut insulated gate static induction transistor comprising a U-shaped groove in a main surface of a semiconductor substrate and a drain region having a high impurity concentration provided so as to contact at least a part of an upper end of a side wall of said U-shaped groove, a source region having a high impurity concentration provided so as to contact at least a part of a lower end of the side wall of said U-shaped groove, a first channel region having a low impurity concentration provided in the vicinity of the surface of the side wall of said U-shaped groove, and a second channel region sandwiched between said drain region and said source region and having the conductivity type different from that of said drain region and said source region, characterized in that the impurity concentration thereof is set so as to eleminate a current flowing through said second channel region, and a current flowing through said firsg channel region is controled by an insulated gate provided on at least a part of said U-shaped groove.
Claim 19
Dependent Claim
178 words
A step-cut insulated gate static induction transistor comprising a U-shaped groove in a main surface of a semiconductor substrate and a drain region having a high impurity concentration provided so as to contact at least a part of an upper end of a side wall of said U-shaped groove, a source region having a high impurity concentration provided so as to contact at least a part of a lower end of the side wall of said U-shaped groove, a first channel region having a low impurity concentration provided in the vicinity of the surface of the side wall of said U-shaped groove, and a second channel region sandwiched between said drain region and said source region and having the conductivity type different from that of said drain region and said source region, characterized in that the impurity concentration thereof is set so as to eleminate a current flowing through said second channel region, and a current flowing through said firsg channel region is controled by an insulated gate provided on at least a part of said U-shaped groove.
Claim 20
Dependent Claim
30 words
A step-cut insulated gate static induction transistor according to Claim 13 wherein said first channel region is formed by the epitaxial growth on the side wall of said U-shaped groove.
Claim 21
Dependent Claim
23 words
A step-cut insulated gate static induction transistor according to Claim 13 or 14 wherein the drain region is exchanged with the source region.
Claim 22
Dependent Claim
31 words
A step-cut insulated gate static induction transistor according to any of Claim 13 to 15 wherein said transistor comprises at least a part of constituent element of the semiconductor integrated circuit.
References Cited (Backward Citations)
No citation records indexed.
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