Hybrid optical proximity correction: concepts and results

Abstract

Optical Proximity Correction (OPC) is increasingly important in the design and manufacturing of integrated circuits, since many of them now contain features which are smaller than the wavelength of light used in lithography. The optical distortions that beset these subwavelength designs are counteracted through the use of OPC, which strategically applies complex corrections to the original features using either a rule-based or model-based approach. Model-based OPC (MOPC) can be very accurate but it suffers from poor speed. Rule-based OPC (ROPC), on the other hand, can convert layouts quickly but at the expense of accuracy. A new concept for optical proximity correction, Hybrid OPC (HOPC), is proposed for enabling the user to control the tradeoff between accuracy and speed of conversion at a fine-grain level of details. Based on feature context, shape, and geometric information such as widths and spacings, HOPC technique can selectively apply MOPC to the most critical regions of the design while allowing the application of ROPC elsewhere. In this paper, we will describe the approach taken as well as provide benchmark data demonstrating the effectiveness of the concept.