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US4808542A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the stabilization of PN junctions

Assignee: Siemens AG
•
Filing: 1987-08-10
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Granted: 1989-02-28
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Expires: 2007-08-10
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Abstract

Abstract In a process for the stabilization of a PN junction an oxide layer (12) is produced on a semiconductor substrate (11), and above this layer a nitride layer (13) is also produced. The oxide layer (12) is wet-chemically etched following the formation and etching of the nitride layer (13). Following the wet chemical etching of the oxide layer (12), the overlapping nitride (13) is re-etched. Dopant implantation takes place in the wet-chemically-etched region. This then is followed by a diffusion. A process of this type achieves high electrical stability for an electronic component. Thereupon, the photoresist (14) or any other type of layer covering the nitride (13) is removed.

Inventors

  • 👤 Hansjoerg Reichert
  • 👤 Ludwig Scharf
  • 👤 Margarete Deckers

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:41
CPC Classifications
H; H10; H10P; H10P76/00; H10P76/40; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/65; H10P14/6516; H10P14/6518; H10P14/6524; H10P14/6526; H10P14/6529; H10P14/69; H10P14/692; H10P14/6921; H10P14/69215; H10P14/694; H10P14/6943; H10P14/69433

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 164 words
A method for the stabilization of a PN junction, the method comprising the steps of: (a) providing an oxide layer on a semiconductor substrate located above an area of a first doping type; (b) producing a nitride layer on the oxide layer; (c) patterning the nitride layer photolithographically by means of a photoresist to produce at least one exposed area of the nitride layer and etching the at least one exposed area to form at least one window in the nitride layer; (d) chemically etching the oxide layer via the at least one window to remove at least one exposed portion of the oxide layer while producing an overlapping nitride region around the window; (e) re-etching, subsequent to the step of chemical etching of the oxide, the overlapping nitride region; (f) via the window, implanting particles of a second doping type, which is opposite to those of the first doping type, followed by a diffusion; and, (g) subsequently removing the photoresist from the nitride.
Claim 2
Independent Claim 164 words
A method for the stabilization of a PN junction, the method comprising the steps of: (a) providing an oxide layer on a semiconductor substrate located above an area of a first doping type; (b) producing a nitride layer on the oxide layer; (c) patterning the nitride layer photolithographically by means of a photoresist to produce at least one exposed area of the nitride layer and etching the at least one exposed area to form at least one window in the nitride layer; (d) chemically etching the oxide layer via the at least one window to remove at least one exposed portion of the oxide layer while producing an overlapping nitride region around the window; (e) re-etching, subsequent to the step of chemical etching of the oxide, the overlapping nitride region; (f) via the window, implanting particles of a second doping type, which is opposite to those of the first doping type, followed by a diffusion; and, (g) subsequently removing the photoresist from the nitride.
Claim 3
Dependent Claim 13 words
A method as defined by claim 1, wherein the semiconductor substrate comprises silicon.
Claim 4
Dependent Claim 13 words
A method as defined in claim 2, wherein the oxide comprises silicon oxide.
Claim 5
Dependent Claim 13 words
A method as defined in claim 2, wherein the nitride comprises silicon nitride.
Claim 6
Dependent Claim 20 words
A method as defined in claim 1, comprises producing a step profile of the oxide and nitride double passivation layer.
Claim 7
Dependent Claim 19 words
A method as defined in claim 1, wherein the oxide layer has a thickness of more than 100 nm.
Claim 8
Dependent Claim 19 words
A method as defined in claim 2, wherein the oxide layer has a thickness of more than 100 nm.
Claim 9
Dependent Claim 19 words
A method as defined in claim 2 wherein the nitride layer has a thickness of more than 100 nm.
Claim 10
Dependent Claim 13 words
A method as defined in claim 1, wherein the oxide comprises silicon oxide.
Claim 11
Dependent Claim 13 words
A method as defined in claim 9, wherein the nitride comprises silicon nitride.
Claim 12
Dependent Claim 19 words
A method as defined in claim 9, wherein the oxide layer has a thickness of more than 100 nm.
Claim 13
Dependent Claim 19 words
A method as defined in claim 9 wherein the nitride layer has a thickness of more than 100 nm.
Claim 14
Dependent Claim 13 words
A method as defined in claim 1, wherein the nitride comprises silicon nitride.
Claim 15
Dependent Claim 19 words
A method as defined in claim 13, wherein the oxide layer has a thickness of more than 100 nm.
Claim 16
Dependent Claim 19 words
A method as defined in claim 13 wherein the nitride layer has a thickness of more than 100 nm.
Claim 17
Dependent Claim 19 words
A method as defined in claim 1 wherein the nitride layer has a thickness of more than 100 nm.
Claim 18
Independent Claim 145 words
A method for stabilizing a PN junction, the method comprising the steps of: (a) providing an oxide layer on a surface of a semiconductor wafer, the surface being located above an area of a first doping type in the semiconductor wafer; (b) providing a nitride layer on the oxide layer; (c) providing a patterned layer on the nitride layer to produce at least one exposed portion; (d) etching the exposed portion of the nitride layer to expose the oxide layer; (e) chemically etching the exposed portion of the oxide layer while peripherally undercutting and forming an overhanging nitride region; (f) etching the overhanging nitride region; (g) implanting particles of a second doping type, which is opposite to those of first doping type into a portion of the area corresponding to removed nitride, followed by a diffusion; and, (h) removing the patterned layer from the nitride.
Claim 19
Independent Claim 145 words
A method for stabilizing a PN junction, the method comprising the steps of: (a) providing an oxide layer on a surface of a semiconductor wafer, the surface being located above an area of a first doping type in the semiconductor wafer; (b) providing a nitride layer on the oxide layer; (c) providing a patterned layer on the nitride layer to produce at least one exposed portion; (d) etching the exposed portion of the nitride layer to expose the oxide layer; (e) chemically etching the exposed portion of the oxide layer while peripherally undercutting and forming an overhanging nitride region; (f) etching the overhanging nitride region; (g) implanting particles of a second doping type, which is opposite to those of first doping type into a portion of the area corresponding to removed nitride, followed by a diffusion; and, (h) removing the patterned layer from the nitride.

References Cited (Backward Citations)

US3764423A Cited
US3771218A Cited
US4084987A Cited
US4135954A Cited
US4244752A Cited
US4442592A Cited
US4635090A Cited
US4412378A Cited
US4382827A Cited
GB2168194A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-02-28 1992-08-29 1993-02-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-02-28 1996-08-29 1997-02-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-02-28 2000-08-29 2001-02-28 $7700.00 Window Closed / Lapsed

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