International Business Machines Corporation

James Allan Bruce

Edward W Conrad

Orest Bula

Steven J Holmes

Robert K Leidy

Michael Straight Hibbs

William C Leipold

Randy William Mann

Jacek G Smolinski

Joshua J Krueger

Jed Hickory Rankin

Kirk David Peterson

Kenneth T Settlemyer, Jr

Walter E Mlynko

Gregory J Dick

Edward W Sengle

Edward J Nowak

Brent A Anderson

David V Horak

John J Ellis-Monaghan

Charles W Koburger, Iii

James William Adkisson

John Joseph Pekarik

James Spiros Nakos

Robert Andrew Myers

James A Culp

Peter H Mitchell

Harold G Linde

Scott Marshall Mansfield

Ioana C Graur

Ranee W Kwong

Jonathan Daniel Chapple-Sokol

Harbans S Sachdev

Michael James Lercel

Andrew J Watts

Matthew C Nicholls

Emily E Fisch

Michael L Kerbaugh

Premlatha J Jagannathan

Stephen E Knight

Mary Conroy Bushey

Joseph Edward Gortych

Dianne L Sundling

Donald P Perley

Walter E Mlyriko

Tanya N Lee

John D Nickel

Rajesh G Narechania

The subject matter disclosed herein relates to determining a lithographic set point using simulations of optical proximity correction verification. In one embodiment, a computer-implemented method of determining a lithographic tool set point for a lithographic process is disclosed. The method may include: providing a model of a production lithographic process including simulations of printed shapes; analyzing the model of the production lithographic process to determine whether a set of structures on a production mask used in the production lithographic process to create the printed shapes will fail under a plurality of set points; determining an operating region of set points where the set of structures on the production mask does not fail; and establishing a set point location within the operating region based upon a set point selection function.

Determining lithographic set point using optical proximity correction verification simulation

Solutions for diagnosing in-line critical dimension control adjustments in a lithographic process are disclosed. In one embodiment, a method includes: locating a control structure in a data set representing one of a chip or a kerf; simulating component dimensions within a region proximate to the control structure; determining a difference between the simulated component dimensions within the region and target component dimensions within the region; determining whether the difference exceeds a predetermined tolerance threshold; adjusting a simulation condition in response to determining the difference exceeds the predetermined tolerance threshold; and repeating the simulating of the component dimensions within the region, the determining of the difference, and the determining of whether the difference exceeds the predetermined tolerance threshold in response to the adjusting of the simulation condition.

Diagnosing in-line critical dimension control adjustments using optical proximity correction verification

Solutions for accounting for photomask deviations in a lithographic process during optical proximity correction verification are disclosed. In one embodiment, a method includes: identifying a wafer control structure in a data set representing one of a first chip or a kerf; biasing the data set representing the first chip in the case that the wafer control structure is in the data set representing the first chip; biasing the data set representing the kerf or a second chip distinct from the first chip, in the case that the wafer control structure is in the data set representing the kerf or the second chip; simulating formation of the wafer control structure; determining whether the simulated wafer control structure complies with a target control structure; and iteratively adjusting an exposure dose condition in the case that the simulated wafer control structure does not comply with the target control structure.

Optical proximity correction verification accounting for mask deviations

The present invention provides a method and computer program product for designing an electrically testable pattern that is based on patterns derived from the desired chip layout to be printed. Such electrical test patterns are based on the features within a region of influence around critical sites. The critical sites may be identified, for example, by processing the chip layout through an OPC verification tool that flags potential failure sites. The electrical test pattern is formed from features within an region of influence (ROI) around the critical site, and also include electrical feed lines at terminal ends of one or more features having an electrical characteristic that is sensitive to changes in the printed environment of the critical site. The feed lines may be locate on the same or a different layer than the critical site, depending on the chip design. The electrical pattern is further defined by retaining features within a second trim region such that the printed features within the ROI are not substantially modified by the absence of features outside the second trim region.

Method for creating electrically testable patterns

Solutions for verifying photomask designs are disclosed. In one embodiment, a method of verifying a photomask design includes: simulating an initial semiconductor manufacturing process using a plurality of mask shapes and variation models for the initial semiconductor manufacturing process, to generate a plurality of contours for the initial semiconductor manufacturing process; simulating a subsequent semiconductor manufacturing process using the contours for the initial semiconductor manufacturing process and variation models for the subsequent semiconductor manufacturing process, to generate a plurality of contours for the subsequent semiconductor manufacturing process; repeatedly simulating at least one further subsequent semiconductor manufacturing process using a plurality of contours for the subsequent semiconductor manufacturing process and variation models for the further subsequent semiconductor manufacturing process; and generating and storing a verification result for the photomask design on a computer readable storage medium.

Photomask design verification

A method is provided for performing optical proximity correction ('OPC') verification in which features of concern of a photomask are identified using data relating to shapes of the photomask, an aerial image to be obtained using the photomask, or a photoresist image to be obtained in a photoimageable layer using the photomask. A plurality of areas of the photomask, aerial image or photoresist image are identified which incorporate the identified features of concern, where the plurality of identified areas occupy substantially less area than the total area of the photomask that is occupied by features. Enhanced OPC verification limited to the plurality of identified areas is then performed to identify problems of at least one of the photomask, aerial image or photoresist image.

OPC verification using auto-windowed regions

An automated system for analyzing mask defects in a semiconductor manufacturing process is presented. This system combines results from an inspection tool and design layout data from a design data repository corresponding to each mask layer being inspected with a computer program and a predetermined rule set to determine when a defect on a given mask layer has occurred. Mask inspection results include the presence, location and type (clear or opaque) of defects. Ultimately, a determination is made as to whether to scrap, repair or accept a given mask based on whether the defect would be likely to cause product failure. Application of the defect inspection data to the design layout data for each mask layer being inspected prevents otherwise acceptable wafer masks from being scrapped when the identified defects are not in critical areas of the mask.

Mask defect analysis system

A design verification method, including (a) providing in a design a design electrically conducting line and a design contact region being in direct physical contact with the design electrically conducting line; (b) modeling a simulated electrically conducting line of the design electrically conducting line; (c) simulating a possible contact region of the design contact region, wherein the design contact region and the possible contact region are not identical; and (d) determining that the design electrically conducting line and the design contact region are potentially defective if an interfacing surface area of the simulated electrically conducting line and the possible contact region is less than a pre-specified value.

Design verification

A mask/wafer control structure and an algorithm for placement thereof provide for data placement of measurement control structures, called a PLS, Process limiting Structure, on a mask and a plurality of chips on the wafer which provide for tighter control of both mask manufacture and wafer production by providing the most critical design structures for measurement during creation of the mask, and in the photolithography and etch processes. The PLS structures are located at multiple locations throughout the chip, and so they receive the same data preparation as the chip, and measurement tools are able to measure the same features at each fabrication step from fabrication of the mask to final formation of the etched features. Manufacturing control and the interlock between the wafer fabrication and the mask fabrication are enhanced, allowing for improved quality of the final product.

Mask/wafer control structure and algorithm for placement

A control target structure and method for monitoring the lithographic affects on minimum feature in a lithographic process. The control target uses line array elements having a nominal width. By changing the shape of the line-ends of the elements the control target can be optimized for controlling either focus or dose.

Structure for lithographic focus control features

Method for effecting edge bias correction of topography-induced linewidth variations which are encountered in printed or integrated circuits on substrates or semiconductor devices for electronic packages. The method modifies data for current levels which is predicated on prior level data and models, as to the manner in which topography will affect the resist and/or antireflective coating (ARC) thicknesses, so as to improve upon linewidth (LW) control and, in general, imparting improved processing windows. The method can be implemented in the form of computer-executable instructions which are embodied in one or more program modules stored on computer-usable media.

Method for edge bias correction of topography-induced linewidth variation

A borderless contact to diffusion with respect to gate conductor is provided by employing a double insulating film stack as a mask for defining the gate conductor shapes for the entire chip and providing a relatively thin damage preventing layer on exposed conductive layer following defining the gate conductor shapes. In one embodiment, a borderless contact is provided by forming an insulating layer on a substrate, providing a conductive layer on the insulating layer, providing a second insulating layer on the conductive layer, providing a third insulating layer on the second insulating layer, removing preselected portions of the second and third insulating layers, providing a damage preventing layer in those areas where the second and third insulating layers have been removed, removing preselected portions of the third insulating layer, removing the damage preventing layer, removing exposed portions of the conductive layer, and removing now exposed portions of the second insulating layer.

Borderless contact to diffusion with respect to gate conductor and methods for fabricating

The present invention provides a novel method of forming implants with Projection Gas-Immersion Laser Doping (PGILD) process that overcomes the disadvantages of the prior art methods. In particular, the preferred method applies a reflective coating over features before the application of the PGILD laser. The reflective coating lowers the amount of heat absorbed by the features, improving the reliability of the fabrication process. The preferred method is particularly applicable to the fabrication of field effect transistors (FETs). In this application, a gate stack is formed, and a reflective coating is over the gate stack. An anti-reflective coating (ARC) is then applied over the reflective coating. The anti-reflective coating reduces variability of the photolithographic process used to pattern the gate stack. After the gate stack is patterned, the anti-reflective coating is removed, leaving the reflective coating on the gate stack. The PGILD process can then be used to form source/drain doped regions on the transistors. The reflective coating reduces the amount of heat absorbed by the gate stack, and thus provides an improved method for fabricating transistors.

Method for forming implants in semiconductor fabrication

Growing community of inventors

Williston, VT, United States of America

James Allan Bruce