D2s, Inc.

Intel Corporation

Ryan Pearman

Akira Fujimura

Harold Robert Zable

William E Guthrie

Nagesh Shirali

Abhishek Shendre

Charles Henry Wallace

Swaminathan Sivakumar

Shem Ogadhoh

Robert C Pack

Anatoly Aadamov

Sven Eric Henrichs

Arvind Sundaramurthy

Methods and systems for exposing a desired shape in an area on a surface using a charged particle beam system include determining a local pattern density for the area, based on an original set of exposure information. A pre-proximity effect correction (PEC) maximum dose for the local pattern density is determined, based on a pre-determined target post-PEC maximum dose. The pre-PEC maximum dose may be calculated near an edge of the desired shape. Methods also include modifying the original set of exposure information with the pre-PEC maximum dose to create a modified set of exposure information.

Method and system for determining a charged particle beam exposure for a local pattern density

A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. The area comprises a plurality of pixels, and the original set of exposure information comprises dosages for the plurality of pixels in the area. A backscatter is calculated for a sub area of the area based on the original set of exposure information including the dosages for the plurality of pixels in the area. An increase in dosage for at least one pixel in a plurality of pixels in the sub area is determined, in a location where the backscatter of the sub area is below a pre-determined threshold, thereby increasing the backscatter of the sub area.

Method and system of reducing charged particle beam write time

Methods for exposing a desired shape in an area on a surface using a charged particle beam system include determining a local pattern density for the area of the desired shape based on an original set of exposure information. A backscatter for a sub area is calculated, based on the original set of exposure information. Dosage for at least one pixel in a plurality of pixels in the sub area is increased, in a location where the backscatter of the sub area is below a pre-determined threshold, thereby increasing the backscatter of the sub area. A pre-PEC maximum dose is determined for the local pattern density, based on a pre-determined target post-PEC maximum dose. The original set of exposure information is modified with the pre-PEC maximum dose and the increased dosage of the at least one pixel in the sub area to create a modified set of exposure information.

A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. The area comprises a plurality of pixels, and the original set of exposure information comprises dosages for the plurality of pixels in the area. A backscatter is calculated for a sub area of the area based on the original set of exposure information. A dosage for at least one pixel in a plurality of pixels in the sub area is increased, in a location where the backscatter of the sub area is below a pre-determined threshold, thereby increasing the backscatter of the sub area. A modified set of exposure information is output, including the increased dosage of the at least one pixel in the sub area.

A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. A backscatter is calculated for the area of the pattern based on the exposure information. An artificial background dose is determined for the area. The artificial background dose comprises additional exposure information and is combined with the original set of exposure information creating a modified set of exposure information. A system for exposing a pattern in an area on a surface using a charged particle beam lithography is also disclosed.

A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes determining a local pattern density for the area of the pattern based on an original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PLC maximum dose.

A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes inputting an original set of exposure information for the area and inputting a target post-proximity effect correction (PEC) maximum dose. A local pattern density is calculated for the area of the pattern based on the original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PEC maximum dose.

In some embodiments, data is received defining a plurality of shot groups that will be delivered by a charged particle beam writer during an overall time period, where a first shot group will be delivered onto a first designated area at a first time period. A temperature of the first designated area at a different time period is determined. In some embodiments, the different time period is when secondary effects of exposure from a second shot group are received at the first designated area. In some embodiments, transient temperatures of a target designated area are determined at time periods when exposure from a shot group is received. An effective temperature of the target area is determined, using the transient temperatures and applying a compensation factor based on an amount of exposure received during that time period. A shot in the target shot group is modified based on the effective temperature.

Shaped beam lithography including temperature effects

A method for forming a pattern on a surface using charged particle beam lithography is disclosed, where the shots in an ordered set of input shots are modified within a subfield to reduce either a thermal variation or a maximum temperature of the surface during exposure by the charged particle beam writer. A method for fracturing or mask data processing is also disclosed, where an ordered set of shots is generated which will expose at least one subfield of a surface using a shaped beam charged particle beam writer, and where a temperature or a thermal variation generated on the surface during the exposure of one subfield is calculated. Additionally, a method for forming a pattern on a surface with an ordered set of shots using charged particle beam lithography is disclosed, in which a blanking period following a shot is lengthened to reduce the maximum temperature of the surface.

Method and system for improving critical dimension uniformity using shaped beam lithography

Techniques are disclosed for using sub-resolution phased assist features (SPAF) in a lithography mask to improve through process pattern fidelity and/or mitigate inverted aerial image problems. The technique also may be used to improve image contrast in non-inverted weak image sites. The use of SPAF in accordance with some such embodiments requires no adjustment to existing design rules, although adjustments can be made to enable compliance with mask inspection constraints. The use of SPAF also does not require changing existing fab or manufacturing processes, especially if such processes already comprehend phased shift mask capabilities. The SPAFs can be used to enhance aerial image contrast, without the SPAFs themselves printing. In addition, the SPAF phase etch depth can be optimized so as to make adjustments to a given predicted printed feature critical dimension.

Lithography mask having sub-resolution phased assist features

A method for mask data preparation or mask process correction is disclosed in which a set of charged particle beam shots is determined which is capable of forming a pattern on a surface, wherein critical dimension uniformity (CDU) of the pattern is optimized. In some embodiments the CDU is optimized by varying at least two factors. In other embodiments, model-based techniques are used. In yet other embodiments, the surface is a reticle to be used in an optical lithographic process to form a pattern on a wafer, and CDU on the wafer is optimized.

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San Jose, CA, United States of America

Ryan Pearman