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US5962065A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of forming polysilicon having a desired surface roughness

Assignee: Micron Technology Inc
•
Filing: 1997-09-03
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Granted: 1999-10-05
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Expires: 2017-09-03
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Abstract

Abstract A method for reliably forming polysilicon of a desired surface roughness includes providing a layer of doped or undoped amorphous silicon on a substrate and heating said substrate while monitoring the emission of said substrate and comparing the monitored emission with an expected emission attributable to the heating regime employed. An increase in the monitored emission not attributable to the heating regime signals a transition of the layer of amorphous silicon to rough polysilicon. A decrease in the monitored emission not attributable to the heating regime signals a transition to smooth polysilicon. The increases and decreases in the monitored emission can be used to end the heating regime at the time at which the desired surface roughness of polysilicon is formed, or merely to passively monitor the process.

Inventors

  • 👤 Ronald A. Weimer
  • 👤 Avishai Kepten
  • 👤 Michael Sendler

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 02:21
CPC Classifications
H; H10; H10P; H10P74/00; H10P74/23; H10P74/238; C; C23; C23C; C23C16/00; C23C16/22; C23C16/24; C23C16/56; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/38; H10P14/3802; H10P14/40; H10P14/416; Y; Y10; Y10S; Y10S438/00; Y10S438/964

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 57 words
A method for forming polysilicon having a desired surface roughness, said method comprising: depositing amorphous silicon upon a substrate; heating said substrate; monitoring an emission of said substrate while heating said substrate; and terminating said heating after a time determined in response to said emission; said emission being characteristic of the achievement of said desired surface roughness.
Claim 2
Independent Claim 57 words
A method for forming polysilicon having a desired surface roughness, said method comprising: depositing amorphous silicon upon a substrate; heating said substrate; monitoring an emission of said substrate while heating said substrate; and terminating said heating after a time determined in response to said emission; said emission being characteristic of the achievement of said desired surface roughness.
Claim 3
Dependent Claim 39 words
The method as defined in claim 1, wherein monitoring said emission of said substrate comprises using a single-color pyrometer to monitor said emission of said substrate within a wavelength range from about 10 -2 μm to about 100 μm.
Claim 4
Dependent Claim 38 words
The method as defined in claim 2, wherein monitoring said emission of said substrate comprises using a single-color pyrometer to monitor said emission of said substrate within a wavelength range from about 1 μm to about 10 μm.
Claim 5
Dependent Claim 33 words
The method as defined in claim 2, wherein said substrate is a silicon wafer having a backside and said single-color pyrometer monitors said emission of said wafer from said backside of said wafer.
Claim 6
Dependent Claim 13 words
The method as defined in claim 1 wherein heating said substrate comprises RTA.
Claim 7
Dependent Claim 28 words
The method as defined in claim 1, wherein terminating said heating after said time is conducted at formation of at least some rough polysilicon from said amorphous silicon.
Claim 8
Dependent Claim 25 words
The method as defined in claim 1, wherein terminating said heating after said time is conducted after formation of rough polysilicon from said amorphous silicon.
Claim 9
Dependent Claim 24 words
The method as defined in claim 1, wherein terminating said heating after said time is conducted at formation of at least some smooth polysilicon.
Claim 10
Dependent Claim 21 words
The method as defined in claim 1, wherein terminating said heating after said time is conducted after formation of smooth polysilicon.
Claim 11
Independent Claim 61 words
A method for forming polysilicon having a desired surface roughness, said method comprising: forming amorphous silicon upon a substrate; heating said amorphous silicon upon said substrate; monitoring an emission of said substrate while heating said amorphous silicon upon said substrate; and terminating said heating in response to said emission; said emission being characteristic of the achievement of said desired surface roughness.
Claim 12
Independent Claim 61 words
A method for forming polysilicon having a desired surface roughness, said method comprising: forming amorphous silicon upon a substrate; heating said amorphous silicon upon said substrate; monitoring an emission of said substrate while heating said amorphous silicon upon said substrate; and terminating said heating in response to said emission; said emission being characteristic of the achievement of said desired surface roughness.
Claim 13
Independent Claim 68 words
A method for detecting the conversion of amorphous silicon to polysilicon having a surface roughness, said method comprising: providing a layer of amorphous silicon on a substrate; heating said substrate; measuring an emission of said substrate while heating said substrate; and detecting a first level of said emission representative of conversion of at least a portion of said layer of amorphous silicon to polysilicon having said surface roughness.
Claim 14
Independent Claim 68 words
A method for detecting the conversion of amorphous silicon to polysilicon having a surface roughness, said method comprising: providing a layer of amorphous silicon on a substrate; heating said substrate; measuring an emission of said substrate while heating said substrate; and detecting a first level of said emission representative of conversion of at least a portion of said layer of amorphous silicon to polysilicon having said surface roughness.
Claim 15
Dependent Claim 42 words
The method as defined in claim 11, further including, after detecting said first level of said emission, detecting a second level of said emission representative of conversion of substantially all of said layer of amorphous silicon to polysilicon having said surface roughness.
Claim 16
Dependent Claim 33 words
The method as defined in claim 11, further including, after detecting said first level of said emission, detecting a progressive decrease in said emission representative of the onset of formation of smooth polysilicon.
Claim 17
Dependent Claim 37 words
The method as defined in claim 13, further including, after detecting said progressive decrease in said emission, detecting an end of said progressive decrease in said emission representative of substantial completion of said formation of smooth polysilicon.
Claim 18
Dependent Claim 13 words
The method as defined in claim 11, wherein heating said substrate comprises RTA.
Claim 19
Dependent Claim 42 words
The method as defined in claim 11, wherein measuring said emission of said substrate comprises using a single-color pyrometer to monitor said emission of said substrate, said emission being within a wavelength range from about 10 -2 μm to about 100 μm.
Claim 20
Dependent Claim 41 words
The method as defined in claim 16, wherein measuring said emission of said substrate comprises using a single-color pyrometer to monitor said emission of said substrate, said emission being within a wavelength range from about 1 μm to about 10 μm.

References Cited (Backward Citations)

US4155779A Cited
US4332833A Cited
US5372836A Cited

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