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US4700311A Expired / Lapsed US ⏱️ 0.0 years remaining

System for optimizing process parameters in photoactive semiconductor manufacturing in-situ

Assignee: Hahn Meitner Institut Berlin GmbH
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Filing: 1985-01-25
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Granted: 1987-10-13
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Expires: 2005-01-25
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Abstract

Abstract Materials and systems substantially having photoactive properties are produced with a high quality output and without time losses in the fabrication process. To determine the quality of the photoactive material in situ, conductivity is induced in the material by exciting charge carriers through irradiation, and an electromagnetic field influenced thereby is measured, with the result of the measurement being evaluated by a computer with a corresponding control of actuating members such as valves and controllers. Optimum process parameters are thus found and used for the process.

Inventors

  • 👤 Helmut Tributsch
  • 👤 Gerhard Beck
  • 👤 Marinus Kunst
  • 👤 Udo Kuppers
  • 👤 Hans-Joachim Lewerenz
  • 👤 Jochen Lilie
  • 👤 Andre Werner

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 18:08
CPC Classifications
H; H10; H10F; H10F71/00; H10F71/10; H10F71/103; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02P; Y02P70/00; Y02P70/50; Y10; Y10S; Y10S136/00; Y10S136/29

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 206 words
A method for optimizing process parameters in photoactive semiconductor manufacuring, comprising: (a) continuously forming a layer of semiconductor material which exhibits photoactive properties, the layer growing on a substrate under conditions of controllable process parameters; (b) exposing the growing layer in situ and during the forming step, to an electromagnetic field; (c) repeatedly irradiating the growing layer to excite charge carriers therein, the excitation of charge carriers, inducing a photoconductivity which directly relates to the photoactive property of the growing material and produces variations in the electromagnetic field interacting with the material exposed to it; (d) measuring the variations of the electromagnetic field to generate measured data; (e) supplying to and evaluating in a computer, the measured data; (f) generating signals by the computer corresponding to the optimum photoactive property of the material as it is growing for use in controlling the process parameters; (g) changing one of the process parameters according to the signals, and (h) repeating the steps (c) through (g) a plurality of times, while maintaining the steps (a) and (b), to generate additional measured data for supplying the evaluating in the computer to successively determine and use optimized process parameters all within the period of time needed for forming the entire layer.
Claim 2
Independent Claim 206 words
A method for optimizing process parameters in photoactive semiconductor manufacuring, comprising: (a) continuously forming a layer of semiconductor material which exhibits photoactive properties, the layer growing on a substrate under conditions of controllable process parameters; (b) exposing the growing layer in situ and during the forming step, to an electromagnetic field; (c) repeatedly irradiating the growing layer to excite charge carriers therein, the excitation of charge carriers, inducing a photoconductivity which directly relates to the photoactive property of the growing material and produces variations in the electromagnetic field interacting with the material exposed to it; (d) measuring the variations of the electromagnetic field to generate measured data; (e) supplying to and evaluating in a computer, the measured data; (f) generating signals by the computer corresponding to the optimum photoactive property of the material as it is growing for use in controlling the process parameters; (g) changing one of the process parameters according to the signals, and (h) repeating the steps (c) through (g) a plurality of times, while maintaining the steps (a) and (b), to generate additional measured data for supplying the evaluating in the computer to successively determine and use optimized process parameters all within the period of time needed for forming the entire layer.
Claim 3
Dependent Claim 12 words
A method according to claim 1, including exposing the material with lightwave.
Claim 4
Dependent Claim 13 words
A method according to claim 2, including irradiating the material with white light.
Claim 5
Dependent Claim 13 words
A method according to claim 2, including irradiating the material with monochromatic light.
Claim 6
Dependent Claim 17 words
A method according to claim 1, including using contacts attached to the material for measuring photoconductivity directly.
Claim 7
Dependent Claim 12 words
A method according to claim 1, including exposing the material with electrons.
Claim 8
Dependent Claim 43 words
A method according to claim 1, including exposing the material to microwaves and using a waveguide for supplying said microwaves to and for measuring variations of said microwaves produced by said excited charge carriers in the material by way of a contactless manner.

References Cited (Backward Citations)

US3982049A Cited
US4332833A Cited
US4525375A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-10-12 1991-04-13 1991-10-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-10-12 1995-04-13 1995-10-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-10-12 1999-04-13 1999-10-13 $7700.00 Window Closed / Lapsed

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