High-fidelity curvilinear mask optical proximity correction using tangent angle-arc length curve

Area of Science:

• Semiconductor manufacturing
• Photolithography
• Computational lithography

Background:

• Curvilinear masks offer superior lithography image quality for advanced semiconductor nodes.
• Optical proximity correction (OPC) is crucial for curvilinear masks, with control point selection and manipulation being key steps.
• Current curvilinear mask OPC methods involve complex algorithms and often yield suboptimal print image fidelity.

Purpose of the Study:

• To introduce a simplified and more effective method for curvilinear mask optical proximity correction (OPC).
• To reduce computational complexity and improve the accuracy of pattern reproduction in advanced lithography.

Main Methods:

• Representing the 2D mask boundary using a one-dimensional Tangent Angle-Arc Length (TAAL) curve.
• Introducing the small selection with directional movement (SSDM) method based on the TAAL curve for control point manipulation.
• Comparing the TAAL-based SSDM method against uniform selection and random movement methods.

Main Results:

• The TAAL curve simplifies control point selection and movement direction determination.
• The TAAL-based SSDM method significantly reduces pattern errors (PAE).
• Simulation results show superior performance compared to existing methods.

Conclusions:

• The TAAL curve provides an efficient representation for curvilinear mask boundaries.
• The TAAL-based SSDM method offers a computationally simpler and more accurate approach to curvilinear mask OPC.
• This method holds promise for improving lithography image quality in advanced nodes.