Back to results
US 11,531,273 B2Granted
Lithographic mask correction using volume correction techniques
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsZhiru Yu, Danping Peng, Junjiang Lei, Yuan Fang
Life of this patent
Estimating the term…
Abstract
A method of making a mask includes computing a mask volume correction matrix for a given mask layout to be used to perform a lithography process. The mask volume correction matrix represents a diffraction field for a predetermined thickness of a material of the mask. A simulated mask pattern is computed by applying the mask volume correction matrix to the given mask layout. The simulated mask pattern is provided to a mask making tool.
Claims20
A computer-implemented method of making a mask, the method comprising:
- computing a mask volume correction matrix for a given mask layout to be used to perform a lithography process, wherein
- the mask volume correction matrix represents a diffraction field for a predetermined thickness of a material of the mask, and
- computing the mask volume correction matrix further includes:
- computing a three-dimensional (3D) diffraction field for a test mask based on a rigorous simulation of the interaction of electric fields with the test mask;
- computing a rigorous simulated mask pattern for the test mask using the 3D diffraction field;
- and
- iteratively adjusting the volume kernel based on a difference between a simulated mask pattern for the test mask and the rigorous simulated mask pattern for the test mask or based on a number of iterations, the volume kernel being adjusted until a desired accuracy threshold is obtained or being adjusted until a desired number of iterations are performed;
- computing a simulated mask pattern by applying the mask volume correction matrix to the given mask layout;
- and
- providing the simulated mask pattern to a mask making tool.
7 more elements
A tool for manufacturing a lithography mask, the tool comprising:
- a processor;
- and
- a memory operably connected to the processor, and having a computer-executable instructions stored thereon, the instructions when executed cause the processor to perform a method including:
- computing a characteristic function based on a desired layout of the mask;
- computing volume kernel based on an interaction of electric field with a predetermined thickness of a material of the mask;
- computing a volume compensated two-dimensional (2D) diffraction field for the desired layout of the mask by transforming a multiplicative product of a 2D diffraction field for the desired layout and the characteristic function using the volume kernel;
- computing a simulated mask pattern using the volume compensated 2D diffraction field;
- and
- providing the simulated mask pattern to a mask making tool, wherein computing the volume kernel comprises
- computing a corrected two-dimensional (2D) diffraction field, the corrected 2D diffraction field being represented by:
- Corrected 2D diffraction field=mask volume correction matrix×2D diffraction field=[3D diffraction field×χ(r′)]*G(r,r′), where χ(r′) represents a pattern-dependent characteristic function, G(r,r′) represents a pattern-independent pre-computed kernel, and ‘*’ represents a convolution operation.
8 more elements
A tool for manufacturing a lithography mask, the tool comprising:
- a processor;
- and
- a memory operably connected to the processor, and having a computer-executable instructions stored thereon, the instructions when executed cause the processor to:
- receive a given mask layout;
- compute a mask volume correction matrix for a given mask layout to be used to perform a lithography process, wherein the mask volume correction matrix represents a diffraction field for a predetermined thickness of a material of the mask, and wherein computing the mask volume correction matrix includes:
- calculating the two-dimensional (2D) diffraction field for the given mask layout considering a 2D mask condition;
- extending the 2D diffraction field to the predetermined thickness of the material of the mask to obtain a three-dimensional (3D) diffraction field representing a 3D diffraction field for the given mask layout provided in the material of the mask;
- and
- recomputing a corrected 2D diffraction field at a surface of the mask as a function of the 3D diffraction field;
- compute a simulated mask pattern by applying the mask volume correction matrix to the given mask layout;
- and
- provide the simulated mask pattern to a mask printer.
9 more elements
Dependencies are inferred from the claim text.