Patent application number | Description | Published |
20090089736 | FACILITATING PROCESS MODEL ACCURACY BY MODELING MASK CORNER ROUNDING EFFECTS - An embodiment provides systems and techniques for determining an improved process model which models mask corner rounding (MCR) effects. During operation, the system may receive a mask layout and process data which was generated by applying a photolithography process to the mask layout. The system may also receive an uncalibrated process model which may contain a set of MCR components. Next, the system may identify a set of corners in the mask layout. The system may then modify the mask layout in proximity to the set of corners to obtain a modified mask layout. Alternatively, the system may determine a set of mask layers. Next, the system may determine an improved process model by calibrating the uncalibrated process model using the modified mask layout and/or the set of mask layers, and the process data. | 04-02-2009 |
20090288047 | METHOD AND APPARATUS FOR USING A DATABASE TO QUICKLY IDENTIFY AND CORRECT A MANUFACTURING PROBLEM AREA IN A LAYOUT - One embodiment provides a system for using a database to quickly identify a manufacturing problem area in a layout. During operation, the system receives a first check-figure which identifies a first area in a first layout, wherein the first area is associated with a first feature. Next, the system determines a first sample using the first check-figure, wherein the first sample represents the first layout's geometry within a first ambit of the first check-figure, wherein the first sample's geometry is expected to affect the shape of the first feature. The system then performs a model-based simulation using the first sample to obtain a first simulation-result which indicates whether the first feature is expected to have manufacturing problems. Next, the system stores the first simulation-result in a database which is used to quickly determine whether a second feature is expected to have manufacturing problems. | 11-19-2009 |
20090292508 | METHOD AND APPARATUS FOR MODELING LONG RANGE EUVL FLARE - One embodiment of the present invention provides techniques and systems for modeling long-range extreme ultraviolet lithography (EUVL) flare. During operation, the system may receive an evaluation point in a layout. Next, the system may receive an EUVL model which includes kernels that are discretized at different sampling rates, and which have different sized ambits. Specifically, a kernel that is discretized using a low sampling rate may have a longer range than a kernel that is discretized using a high sampling rate. The system may then convolve the kernels with the layout at the evaluation point over their respective ambits. Next, the system may use the convolution results to determine an indicator value. The indicator value can be used for a number of applications, e.g., to predict pattern shapes that are expected to print on a wafer, to perform optical proximity correction, or to identify manufacturing problem areas in the layout. | 11-26-2009 |
20100086196 | METHOD AND APPARATUS FOR DETERMINING AN OPTICAL THRESHOLD AND A RESIST BIAS - One embodiment of the present invention provides techniques and systems for determining modeling parameters for a photolithography process. During operation, the system can receive a layout. Next, the system can determine an iso-focal pattern in the layout. The system can then determine multiple aerial-image-intensity values in proximity to the iso-focal pattern by convolving the layout with multiple optical models, wherein the multiple optical models model the photolithography process's optical system under different focus conditions. Next, the system can determine a location in proximity to the iso-focal pattern where the aerial-image-intensity values are substantially insensitive to focus variations. The system can then use the location and the associated aerial-image-intensity values to determine an optical threshold and a resist bias. The optical threshold and the resist bias can then be used for modeling the photolithography process. | 04-08-2010 |
20100092880 | METHOD AND APPARATUS FOR USING A SYNCHROTRON AS A SOURCE IN EXTREME ULTRAVIOLET LITHOGRAPHY - One embodiment of the present invention provides a method to facilitate using a synchrotron as a source in an extreme ultraviolet lithography (EUVL) system, wherein the synchrotron's energy decreases over time. The EUVL system can includes a stepper which uses a step-and-repeat process or a step-and-scan process to transfer patterns from a reticle onto a wafer. The wafer is desired to be exposed to a substantially constant dose. During operation, the system can measure a synchrotron current, and adjust the stepper's exposure duration or the stepper's scan speed based on the synchrotron current so that the wafer is exposed to the substantially constant dose. Note that using the synchrotron current to control the stepper can enable the EUVL system to expose the wafer to the substantially constant dose without using additional equipment to monitor the source's energy. | 04-15-2010 |
20100095264 | METHOD AND APPARATUS FOR DETERMINING A PHOTOLITHOGRAPHY PROCESS MODEL WHICH MODELS THE INFLUENCE OF TOPOGRAPHY VARIATIONS - One embodiment provides a system for determining a process model for a photolithography process. The photolithography process can use multiple exposure-and-development steps to create features on a wafer. When the photolithography process exposes the wafer to a layout, the wafer can include topography variations which were caused by previous exposure-and-development steps. The process model can be used to predict patterns that are created on the wafer when the wafer is exposed to a second layout, wherein the wafer includes topography variations that were caused by resist features that were created when the wafer was exposed to a first layout. The process model can include a first term and a second term, wherein the first term is convolved with a sum of the first layout and the second layout, and wherein the second term is convolved with the second layout. | 04-15-2010 |
20100146476 | MODELING MASK CORNER ROUNDING EFFECTS USING MULTIPLE MASK LAYERS - An embodiment provides systems and techniques for determining an improved process model which models mask corner rounding (MCR) effects. During operation, the system may receive a mask layout and process data which was generated by applying a photolithography process to the mask layout. The system may also receive an uncalibrated process model which may contain a set of MCR components. Next, the system may identify a set of corners in the mask layout. The system may then determine a set of mask layers, wherein at least some of the mask layers correspond to the MCR components. Next, the system may determine an improved process model by calibrating the uncalibrated process model using the set of mask layers, and the process data. | 06-10-2010 |
20100191518 | COMPACT ABBE'S KERNEL GENERATION USING PRINCIPAL COMPONENT ANALYSIS - Some embodiments provide techniques for determining a set of Abbe's kernels which model an optical system of a photolithography process. During operation, the system can receive optical parameters (e.g., numerical aperture, wavelength, etc.) for the photolithography process's optical system. Next, the system can use the optical parameters to determine a point spread function for an Abbe's source. Note that the point spread function for the Abbe's source can be determined either by discretizing the optical system's light source using a set of concentric circles, or by discretizing the optical system's light source in an orthogonal fashion. The system can then determine a correlation matrix from the point spread function. Next, the system can determine the set of Abbe's kernels by performing an eigen decomposition of the correlation matrix using principal component analysis. The system can then use the set of Abbe's kernels to compute image intensity. | 07-29-2010 |
20100218160 | METHOD AND APPARATUS FOR DETERMINING A PROCESS MODEL THAT MODELS THE IMPACT OF A CAR/PEB ON THE RESIST PROFILE - An embodiment provides systems and techniques for determining a process model. During operation, the system may receive a first optical model which models a first optical system of a photolithography process. Next, the system may use the first optical model to determine a second optical model that models a second latent image that is formed by the first optical system at a second distance. The system may also use the first optical model to determine a third optical model that models a third latent image that is formed by the first optical system at a third distance. Next, the system may receive process data which is obtained by subjecting a test layout to the photolithography process. The system may then determine a process model using the first optical model, the second optical model, the third optical model, the test layout, and the process data. | 08-26-2010 |
20110224963 | Fast Photolithography Process Simulation to Predict Remaining Resist Thickness - A lithography model uses a transfer function to map exposure energy dose to the thickness of remaining photoresist after development; while allowing the flexibility to account for other physical processes. In one approach, the model is generated by fitting empirical data. The model may be used in conjunction with an aerial image to obtain a three-dimensional profile of the remaining photoresist thickness after the development process. The lithography model is generally compact, yet capable of taking into account various physical processes associated with the photoresist exposure and/or development process for more accurate simulation. | 09-15-2011 |
20140244226 | COMPACT OPC MODEL GENERATION USING VIRTUAL DATA - A method, system or computer usable program product for building a fast lithography OPC model that predicts semiconductor manufacturing process outputs on silicon wafers including providing a first principles model of the semiconductor manufacturing process, providing a set of empirical data for storage in memory, utilizing a processor to develop a rigorous model for a process condition from the first principles model and the set of empirical data, and utilizing the processor running the rigorous model to generate emulated data for the process condition to develop a virtual model for predicting the semiconductor manufacturing process outputs. | 08-28-2014 |