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EP0252888A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Photopolymer multilayer structure for the production of a GaAs self aligning double recess

Assignee: Leonardo SpA
•
Filing: 1987-06-26
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Granted: —
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Expires: 2007-06-26
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Abstract

Abstract Technological process for the production of a GaAs self aligning double recess to be applied to power MESFET devices. The process consists of a first exposure of the planarizing layer to define the length of the first recess, into which the gate is set and is followed by a second exposure of the same photopolymer to define the length of the second recess. The resulting double recess structure, through suitable dimensioning, related to the active channel doping, gives way to high power MESFET devices; in particular it makes possible the application of high source to drain voltages (VDS typically 60 DIVIDED 80 V) to the device before breakdown processes are triggered.

Inventors

  • 👤 Antonio Cetronio
  • 👤 Sergio Moretti
  • 👤 D'eustacchio Patrizio

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-02 16:03
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/061; H10D30/0612; H10D30/80; H10D30/87; H10D30/877; H10P; H10P50/00; H10P50/69; H10P50/691; H10P50/692; H10P50/693; H10P50/694

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 103 words
Photopolymer multilayer structure for the production of a self aligning double recess characterized by the following process: a) exposure of planarizing photopolymer (8) to set the length of first recess (7); b) substrate (such as GaAs) erosion through suitable chemical solution (such as NH 4 0H-H 2 0 2 - H 2 0 ) ; c) further exposure of planarizing photopolymer (8) to set the length of the seond recess (12); d) further erosion of the substrate (such as GaAs) by means of a suitable solution (such as NH 4 OH-H 2 O 2 -H 2 O) to produce the second recess (12).
Claim 2
Dependent Claim 103 words
Photopolymer multilayer structure for the production of a self aligning double recess characterized by the following process: a) exposure of planarizing photopolymer (8) to set the length of first recess (7); b) substrate (such as GaAs) erosion through suitable chemical solution (such as NH 4 0H-H 2 0 2 - H 2 0 ) ; c) further exposure of planarizing photopolymer (8) to set the length of the seond recess (12); d) further erosion of the substrate (such as GaAs) by means of a suitable solution (such as NH 4 OH-H 2 O 2 -H 2 O) to produce the second recess (12).
Claim 3
Dependent Claim 23 words
Photopolymer multilayer structure to produce a double recess, as per claim 1, where such process may be applied to any type of substrate.
Claim 4
Dependent Claim 40 words
Photopolymer multilayer structure, as per claim 1 & 2, characterized by the fact that among the many applications of the process, such as in the case of MESFET devices, it is possible to prodceand therefore utilize an asymmetrical double recess.
Claim 5
Dependent Claim 32 words
Photopolymer multilayer structure to produce a self aligning double recess, characterized by the fact that it may be produced by a Multilayer Resist structure as determined by Patent Application N. 47648 A/86.
Claim 6
Dependent Claim 32 words
Photopolymer multilayer structure to produce a self aligning double recess, characterized by the fact that it may be produced by a Multilayer Resist structure as determined by Patent Application N. 47648 A/86.

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