Kla Tencor Corporation

Jingyi Xiong

Zhongping Cai

Anatoly Romanovsky

Alexander Slobodov

Paul Doyle

Tyler Trytko

A system for substrate tilt and focus control in an inspection system includes a dynamically actuatable substrate stage assembly including a substrate stage for securing a substrate; a tilt-height detection system including: a height detection sub-system and a tilt detection sub-system. The system further includes a first actuator configured to selectably actuate the substrate along a direction perpendicular to the surface of the substrate at a location of the substrate stage assembly; and an additional actuator configured to selectably actuate the substrate along a direction substantially perpendicular to the surface of the substrate at an additional location of the substrate stage assembly; and a MIMO tilt-focus controller communicatively coupled to the height detection sub-system, the tilt detection sub-system, the first actuator and the additional actuator.

Method and system for simultaneous tilt and height control of a substrate surface in an inspection system

High speed height control of a surface of a substrate within a wafer inspection system includes positioning a substrate on a substrate stage of a dynamically adjustable substrate stage assembly, actuating the substrate perpendicular to the surface of the substrate, measuring a height error value of the surface of the substrate at a position of inspection of the surface, measuring a displacement value perpendicular to the surface of the substrate at the location of the substrate stage assembly, generating a displacement target from the height error value and the displacement value, and adjusting an actuation state of the actuator using the measured height error value and the generated displacement target in order to maintain the substrate surface at an imaging plane of a detector of the inspection system or a focus of illumination of the inspection system.

Growing community of inventors

Sunnyvale, CA, United States of America

Jingyi Xiong