Patent ID: 8804100
Filing Date: 2014-08-12
Classification: G03F

Abstract:
1. A method for determining one or more focus parameters for an exposure system, the exposure system being used in photolithographic processes in manufacturing integrated circuits, the method comprising: forming a first plurality of patterns and a second plurality of patterns using the exposure system on a semiconductor wafer, each of the plurality of patterns being associated with one or more known focus parameters, wherein the first plurality of patterns is configured such that a focused portion thereof is shifted in a first direction when the exposure system is out of focus, and the second plurality of patterns is configured such that a focused portion thereof is shifted in a second direction opposite the first direction when the exposure system is out of focus; obtaining characteristics for each of the first plurality and the second plurality of patterns using an optical measuring device; and determining a focus position for the exposure system associated with a minimal relative shift, wherein forming the first plurality of patterns includes forming the following plurality of lines and spaces in an order along a first direction: wherein forming the second plurality of patterns includes forming said plurality of lines and spaces in an opposite order along the first direction.