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US4068016A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for regulating evaporating rate and layer build up in the production of thin layers

Assignee: Individual
•
Filing: 1975-03-11
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Granted: 1978-01-10
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Expires: 1995-03-11
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Abstract

Abstract An arrangement for regulating the evaporation rate and the layer buildup in the production of optically effective thin layers in a vacuum on substrates with controlled evaporator power and with continuous measuring of the optical characteristics of the deposited layer. The evaporation is started with a given evaporator power and with the start of change of the optical characteristics of the layer, the measured result after forming the time derivative is continuously compared with the output signal of a signal generator. This output signal reproduces the time rate of change of the optical properties during the layer buildup. The difference signal of the comparison signal is used to increase the evaporator power if the layer buildup lags, and to reduce this power if the layer buildup is too fast.

Inventors

  • 👤 Ingo G. Wilmanns

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 19:32
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/54; C23C14/542; C23C14/545; C23C14/547

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 216 words
A method for regulating the evaporation rate and layer buildup in the production of optically effective thin layer comprising the steps of: inserting a substrate of which thin layers are to be produced into a vacuum chamber; applying evaporating power for deposition of a layer on said substrate and controlling said evaporation power, said evaporating power corresponding to power applied to an evaporating device for evaporating the material of said layer prior to deposition; measuring the optical characteristics of the deposited layer; starting the evaporation with a predetermined power; forming the time derivative of the measurement resulting from measuring the optical characteristics of the deposited layer after the optical characteristics of the layer start to change; generating a predefined sinusoidal signal corresponding to the time rate of change of the optical characteristics of the layer during the layer buildup under predetermined optimum conditions and being independent from the optical characteristics of the layer being deposited; comparing continuously the time derivative of said measured result with said generated signal; generating a difference signal from said comparison step for regulating said power in accordance with the layer buildup so that the power is increased when layer buildup lags and power is reduced when layer buildup is too rapid; said layer being substantially constant as a function of time.
Claim 2
Independent Claim 216 words
A method for regulating the evaporation rate and layer buildup in the production of optically effective thin layer comprising the steps of: inserting a substrate of which thin layers are to be produced into a vacuum chamber; applying evaporating power for deposition of a layer on said substrate and controlling said evaporation power, said evaporating power corresponding to power applied to an evaporating device for evaporating the material of said layer prior to deposition; measuring the optical characteristics of the deposited layer; starting the evaporation with a predetermined power; forming the time derivative of the measurement resulting from measuring the optical characteristics of the deposited layer after the optical characteristics of the layer start to change; generating a predefined sinusoidal signal corresponding to the time rate of change of the optical characteristics of the layer during the layer buildup under predetermined optimum conditions and being independent from the optical characteristics of the layer being deposited; comparing continuously the time derivative of said measured result with said generated signal; generating a difference signal from said comparison step for regulating said power in accordance with the layer buildup so that the power is increased when layer buildup lags and power is reduced when layer buildup is too rapid; said layer being substantially constant as a function of time.
Claim 3
Dependent Claim 39 words
A method as defined in claim 1 wherein said sinusoidal signal comprises a signal having a decreasing amplitude with time and an axis directed downward with time, so that the ordinates of the axis decrease in magnitude with time.
Claim 4
Dependent Claim 28 words
The method as defined in claim 1 including the step of detecting the change of absorption and reflection while retaining constant the deposited mass per unit of time.

References Cited (Backward Citations)

GB990211A Cited
US3347701A Cited
FR1364093A Cited
US3382842A Cited
US3636916A Cited
US3853093A Cited
US3670693A Cited
US3773548A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-01-09 1981-07-11 1982-01-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-01-09 1985-07-11 1986-01-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-01-09 1989-07-11 1990-01-10 $7700.00 Window Closed / Lapsed

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