Measurement of Spacing Checks in Guardian DRC

Introduction

In previous versions of Guardian DRC there were only two ways of measuring the distance between two segments: the ordinary, Euclidean metric, and the square metric, which behaves differently when measuring distances from a corner of a shape. With decreasing feature sizes Euclidean metric does not always provide the adequate measurement of tolerances required during the IC fabrication. Therefore various DRC systems introduced other types of measurement. This article describes how Guardian DRC system performs measurements required for the execution of DRC spacing checks, which are based on separations between line segments (“width”, “indistance”, “outdistance”, “ovdistance”, “distance”, “compdistance”).