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US6238830B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Active control of temperature in scanning probe lithography and maskless lithograpy

Assignee: GlobalFoundries Inc
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Filing: 1999-10-29
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Granted: 2001-05-29
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Expires: 2019-10-29
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Abstract

Abstract A system for monitoring and regulating a photoresist temperature in a maskless lithography pattern transfer process is disclosed. The system includes a photoresist layer overlying a substrate and a material associated with the photoresist layer, wherein the material exhibits a transformation over variations in temperature. The system also includes a detection system for detecting the transformation in the material and a processor operatively coupled to the detection system. The processor receives information associated with the detected transformation and uses the information to control a tool being used for the pattern transfer, thereby reducing variations in temperature in the resist during pattern transfer. In addition, a method of monitoring and regulating a photoresist temperature in a maskless lithography pattern transfer process is disclosed. The method includes associating a material having a characteristic which varies over variations in temperature with a photoresist layer which overlies a substrate and detecting the characteristic during the pattern transfer process. Once detected a temperature of a portion of the photoresist layer is determined using the detected characteristic and an operation of a writing tool which performs the pattern transfer process in response to the photoresist layer temperature is controlled in response thereto.

Inventors

  • 👤 Bharath Rangarajan
  • 👤 Michael K. Templeton
  • 👤 Bhanwar Singh

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 10:21
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/708; G03F7/70858; G03F7/70866; G03F7/70875; G01; G01Q; G01Q30/00; G01Q30/08; G01Q30/10; G01Q80/00; H; H01; H01J; H01J2237/00; H01J2237/30; H01J2237/317; H01J2237/3175; H01J2237/31752; H01J2237/31759; Y; Y10; Y10S; Y10S977/00; Y10S977/84; Y10S977/849; Y10S977/855

Claims Analysis

Total Claims: 41
Claim 1
Independent Claim 87 words
A system for monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising: a photoresist layer overlying a substrate; a material associated with the photoresist layer, wherein the material exhibits a characteristic which varies over variations in temperature; a detection system for detecting the material characteristic; and a processor operatively coupled to the detection system, the processor configured to receive information associated with the detected characteristic and use the information to control a tool being used for the pattern transfer process.
Claim 2
Independent Claim 87 words
A system for monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising: a photoresist layer overlying a substrate; a material associated with the photoresist layer, wherein the material exhibits a characteristic which varies over variations in temperature; a detection system for detecting the material characteristic; and a processor operatively coupled to the detection system, the processor configured to receive information associated with the detected characteristic and use the information to control a tool being used for the pattern transfer process.
Claim 3
Dependent Claim 14 words
The system of claim 1 , wherein the material is in the photoresist layer.
Claim 4
Dependent Claim 14 words
The system of claim 1 , wherein the material is below the photoresist layer.
Claim 5
Dependent Claim 13 words
The system of claim 1 , wherein the material overlies the photoresist layer.
Claim 6
Dependent Claim 14 words
The system of claim 1 , wherein the material comprises a temperature sensitive fluorophore.
Claim 7
Dependent Claim 23 words
The system of claim 5 , wherein the characteristic is a fluorescence having a wavelength that varies with respect to changes in temperature.
Claim 8
Dependent Claim 12 words
The system of claim 6 , wherein the fluorophore comprises europium chelate.
Claim 9
Dependent Claim 22 words
The system of claim 5 , wherein the characteristic is fluorescence having an intensity that varies with respect to changes in temperature.
Claim 10
Dependent Claim 45 words
The system of claim 1 , wherein the detection system comprises: a detector which senses the material characteristic; and a measuring system operatively coupled to the detector, wherein the measuring system converts the detected material characteristic into a data form for processing by the processor.
Claim 11
Dependent Claim 16 words
The system of claim 9 , wherein the measuring system comprises an analog to digital converter.
Claim 12
Dependent Claim 12 words
The system of claim 9 , wherein the detector comprises a spectrometer.
Claim 13
Dependent Claim 12 words
The system of claim 9 , wherein the detector comprises a photodetector.
Claim 14
Dependent Claim 28 words
The system of claim 1 , wherein the processor is further configured to determine a temperature at a portion of the photoresist layer based on the detected characteristic.
Claim 15
Dependent Claim 46 words
The system of claim 13 , wherein the processor is further configured to compare the temperature to an acceptable temperature range and generate control instructions based on the comparison, wherein the control instructions are used to control the tool being used for the pattern transfer process.
Claim 16
Dependent Claim 24 words
The system of claim 14 , wherein the control instructions dictate a write rate for the tool being used for the pattern transfer process.
Claim 17
Dependent Claim 50 words
The system of claim 1 , wherein the tool being used for the pattern transfer process is selected from the group consisting of an ion beam lithography tool, an electron beam lithography tool, a scanning tunneling microscope, a scanning force microscope, an atomic force microscope and a scanning probe microscope.
Claim 18
Dependent Claim 45 words
The system of claim 1 , further comprising a pattern driver associated with the processor and the tool, wherein the pattern driver receives control instructions from the process and controls a position and a write rate of the tool in response to the control instructions.
Claim 19
Dependent Claim 21 words
The system of claim 12 , further comprising an excitation source for triggering the characteristic which varies over variations in temperature.
Claim 20
Dependent Claim 24 words
The system of claim 1 , wherein the maskless lithography pattern transfer process is used to fabricate a mask or a semiconductor patterned wafer.
Claim 21
Independent Claim 116 words
A system for monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising: a photoresist layer overlying a substrate; a material associated with the photoresist layer, wherein the material exhibits a characteristic which varies over variations in temperature; a detection and measuring system which detects the material characteristic and converts the characteristic into an electrical signal; a processor operatively coupled to the detection and measuring system, wherein the processor is configured to receive the electrical signal, analyze the electrical signal, and generate a control instruction in response thereto; and a maskless lithography writing tool operatively coupled to the process, wherein the writing tool operates in accordance with the control instruction.
Claim 22
Independent Claim 116 words
A system for monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising: a photoresist layer overlying a substrate; a material associated with the photoresist layer, wherein the material exhibits a characteristic which varies over variations in temperature; a detection and measuring system which detects the material characteristic and converts the characteristic into an electrical signal; a processor operatively coupled to the detection and measuring system, wherein the processor is configured to receive the electrical signal, analyze the electrical signal, and generate a control instruction in response thereto; and a maskless lithography writing tool operatively coupled to the process, wherein the writing tool operates in accordance with the control instruction.
Claim 23
Dependent Claim 26 words
The system of claim 20 , wherein the material comprises a temperature sensitive fluorophore which provides fluorescence in response to being excited by an excitation source.
Claim 24
Dependent Claim 25 words
The system of claim 20 , wherein the electric signal represents a parameter that correlates to a temperature of a portion of the photoresist layer.
Claim 25
Dependent Claim 69 words
The system of claim 20 , wherein the processor is further configured to determine a temperature of a portion the photoresist layer based on the electrical signal and generate the control instruction based on the determined temperature, wherein the control instruction alters a write rate of the writing tool if the determined temperature is outside of a predetermined range to thereby dynamically regulate the temperature of the photoresist layer.
Claim 26
Independent Claim 85 words
A method of monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising the steps of: associating a material having a characteristic which varies over variations in temperature with a photoresist layer which overlies a substrate; detecting the characteristic during the pattern transfer process; determining a temperature of a portion of the photoresist layer using the detected characteristic; and controlling an operation of a writing tool which performs the pattern transfer process in response to the photoresist layer temperature.
Claim 27
Independent Claim 85 words
A method of monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising the steps of: associating a material having a characteristic which varies over variations in temperature with a photoresist layer which overlies a substrate; detecting the characteristic during the pattern transfer process; determining a temperature of a portion of the photoresist layer using the detected characteristic; and controlling an operation of a writing tool which performs the pattern transfer process in response to the photoresist layer temperature.
Claim 28
Dependent Claim 22 words
The method of claim 24 , wherein associating the material with the photoresist layer comprises doping the photoresist layer with the material.
Claim 29
Dependent Claim 22 words
The method of claim 24 , wherein associating the material with the photoresist layer comprises depositing the material under the photoresist layer.
Claim 30
Dependent Claim 22 words
The method of claim 24 , wherein associating the material with the photoresist layer comprises depositing the material over the photoresist layer.
Claim 31
Dependent Claim 36 words
The method of claim 24 , wherein the material comprises a temperature sensitive fluorophore and detecting the characteristic comprises: irradiating the fluorophore; and sensing the fluorescence, wherein the fluorescence is a function of the photoresist temperature.
Claim 32
Dependent Claim 19 words
The method of claim 28 , wherein a wavelength of the fluorescence is a function of the photoresist temperature.
Claim 33
Dependent Claim 19 words
The method of claim 28 , wherein an intensity of the fluorescence is a function of the photoresist temperature.
Claim 34
Dependent Claim 28 words
The method of claim 24 , wherein determining the photoresist temperature comprises calculating the photoresist temperature using a correlation algorithm which correlates the characteristic to the photoresist temperature.
Claim 35
Dependent Claim 61 words
The method of claim 24 , wherein the material is a temperature sensitive fluorophore and wherein detecting the characteristic and determining the photoresist temperature comprises: sensing a wavelength of a fluorescence caused by the temperature sensitive fluorophore, wherein the fluorescence wavelength is a function of the photoresist temperature; and correlating the fluorescence wavelength to the photoresist temperature using a correlation algorithm.
Claim 36
Dependent Claim 61 words
The method of claim 24 , wherein the material is a temperature sensitive fluorophore and wherein detecting the characteristic and determining the photoresist temperature comprises: sensing an intensity of a fluorescence caused by the temperature sensitive fluorophore, wherein the fluorescence intensity is a function of the photoresist temperature; and correlating the fluorescence intensity to the photoresist temperature using a correlation algorithm.
Claim 37
Dependent Claim 47 words
The method of claim 24 , wherein controlling the operation of the writing tool comprises: generating a control instruction in response to the determined photoresist temperature; and transmitting the control instruction to the writing tool, wherein the control instruction controls a write rate of the writing tool.
Claim 38
Dependent Claim 46 words
The method of claim 34 , wherein when the determined photoresist temperature exceeds a predetermined temperature, the generated control instruction reduces a write rate of the writing tool, thereby reducing the generation of heat in a portion of the photoresist layer during the pattern transfer process.
Claim 39
Dependent Claim 47 words
The method of claim 34 , wherein when the determined photoresist temperature is less than a predetermined temperature, the generated control instruction increases a write rate of the writing thereby increasing the generation of heat in a portion of the photoresist layer during the pattern transfer process.
Claim 40
Independent Claim 157 words
A method of monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising the steps of: associating a material having a characteristic which varies over variations in temperature with a photoresist layer which overlies a substrate; initiating a pattern transfer process using a preliminary control routine having a default write rate for one or more writing tools; detecting the characteristic during the pattern transfer process; determining a temperature of a portion of the photoresist layer using the detected characteristic; modifying the default write rate of at least one of the one or more writing tools at one or more locations about the photoresist in response to the determined temperature to maintain the photoresist temperature within a predetermined temperature range; and storing the modified default rate data in a memory, wherein the modified write rate data is used in conjunction with portions of the preliminary control routine to generate the control routine.
Claim 41
Independent Claim 157 words
A method of monitoring and regulating a photoresist temperature in conjunction with a maskless lithography pattern transfer process, comprising the steps of: associating a material having a characteristic which varies over variations in temperature with a photoresist layer which overlies a substrate; initiating a pattern transfer process using a preliminary control routine having a default write rate for one or more writing tools; detecting the characteristic during the pattern transfer process; determining a temperature of a portion of the photoresist layer using the detected characteristic; modifying the default write rate of at least one of the one or more writing tools at one or more locations about the photoresist in response to the determined temperature to maintain the photoresist temperature within a predetermined temperature range; and storing the modified default rate data in a memory, wherein the modified write rate data is used in conjunction with portions of the preliminary control routine to generate the control routine.

References Cited (Backward Citations)

US5504338A Cited
US5618760A Cited
US5784157A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2004-05-28 2004-11-27 2005-05-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2008-05-28 2008-11-27 2009-05-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2012-05-28 2012-11-27 2013-05-29 $7700.00 Window Closed / Lapsed

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