Method of separating a template from a substrate during imprint lithography

• US 20040104641A1
• Filed: 07/10/2003
• Published: 06/03/2004
• Est. Priority Date: 10/29/1999
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System), University of Texas System
• Inventors: Sreenivasan, Sidlgata V., Johnson, Stephen C., Choi, Byung Jin
• Granted Patent: US 6,870,301 B2
• Time in Patent Office: Days
• US Class Current: 310/328
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: G03F 7/0002 Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping
• CPC Class Codes: G03F 9/00 Registration or positioning of originals, masks, frames, photographic sheets or textured or patterned surfaces, e.g. automatically G03F7/22 takes precedence; preparation of photographic masks G03F1/00; within photographic printing apparatus for making copies G03B27/00

Abstract

Processes and associated devices for high precision positioning of a template an substrate during imprint lithography includes a calibration system with a course calibration stage and a fine orientation stage capable of maintaining a uniform gap between the template and substrate. The fine orientation stage includes a pair of flexure members having flexure joints for motion about a pivot point intersected by first and second orientation axes. Actuators lengthen or shorten to expand or contract the flexure members. Separation of the template is achieved using a peel-and-pull method that avoids destruction of imprinted features from the substrate.

Claims

77. A method of separating a template extending in a first plane from a substrate extending in a second plane having an imprinting material disposed on a surface of said substrate, said method comprising:

forming an oblique angle between said first plane and said second plane; and

increasing a distance between said template and said substrate so that said template is spaced-apart from said substrate.

78. The method as recited in claim 77 wherein said angle is achieved by applying a force to said template to cause said template to be tilted with respect to said substrate, wherein said substrate remains stationary.

79. The method as recited in claim 77 wherein said angle is achieved by applying a force to said substrate to cause said substrate to be tilted with respect to said template, wherein said template remains stationary.

80. The method as recited in claim 77 wherein said increasing said distance is achieved by applying a force to said template, wherein said force is applied by a flexure system.

81. The method as recited in claim 77 wherein said increasing said distance is achieved by applying a force to said template, wherein said force is applied by a piezo actuator, wherein said piezo actuator contains a first end and a second end positioned opposite to each other, wherein said first end is attached to said template and said second end is in contact with said substrate, wherein enlarging said piezo actuator causes said template to be pushed away from said substrate.

82. The method as recited in claim 81 wherein said second end is treated with a low surface energy layer.

83. A method of separating a template from a substrate, with a first distance and a second distance defined therebetween, wherein said first distance is defined opposite to said second distance, said method comprising:

increasing a first spacing between said substrate and said template so that a rate of change of said first distance is at a higher rate than a rate of change of said second distance; and

increasing a second spacing between said substrate and said template so that a rate of change of said first distance and said second distance are substantially uniform.

84. The method as recited in claim 83 wherein said increasing said first distance is achieved by applying a force to said template to cause a wedge between said template and said substrate at one end of a template-substrate interface, wherein said template is to be tilted with respect to said substrate and said substrate remains stationary.

85. The method as recited in claim 83 wherein said increasing said first distance is achieved by applying a force to said template to cause a wedge between said template and said substrate at one end of said template-substrate interface, wherein said substrate is to be tilted with respect to said template and said template remains stationary.

86. The method as recited in claim 83 wherein said increasing said second distance is achieved by applying a force to said template to cause said template to be substantially separated from said substrate.

87. The method as recited in claim 83 wherein said increasing said second distance is achieved by applying a force to said template, wherein said force is applied by a flexure system.

88. The method as recited in claim 83 wherein said increasing said second distance is achieved by applying a force to said template, wherein said force is applied by a piezo actuator, wherein said piezo actuator contains a first end and a second end positioned opposite to each other, wherein said first end is attached to said template and said second end is in contact with said substrate, wherein enlarging said piezo actuator causes said template to be pushed away from said substrate.

89. The method as recited in claim 88 wherein said second end is treated with a low surface energy layer.

90. A method of separating a template extending in a first plane from an imprinting layer extending in a second plane, said method comprising:

forming an oblique angle between said first plane and said second plane to cause a wedge between said template and said imprinting layer at one end of a template-imprinting layer interface; and

increasing a distance between said template and said imprinting layer so that said template is spaced-apart from said imprinting layer.

91. The method as recited in claim 90 wherein said angle is achieved by applying a force to said template to cause said template to be tilted with respect to said imprinting layer, wherein said imprinting layer remains stationary.

92. The method as recited in claim 90 wherein said angle is achieved by applying a force to said imprinting layer to cause said imprinting layer to be tilted with respect to said template, wherein said template remains stationary.

93. The method as recited in claim 90 wherein said increasing said distance is achieved by applying a force to said template, wherein said force is applied by a flexure system.

94. The method as recited in claim 90 wherein said increasing said distance is achieved by applying a force to said template, wherein said force is applied by a piezo actuator, wherein said piezo actuator contains a first end and a second end positioned opposite to each other, wherein said first end is attached to said template and said second end is in contact with said imprinting layer, wherein enlarging said piezo actuator causes said template to be pushed away from said imprinting layer.

95. The method as recited in claim 94 wherein said second end is treated with a low surface energy layer.