Kla-Tencor Technologies Corporation

Kla Tencor Corporation

Jun Pei

Mark Armstrong McCord

Neil W Richardson

David J Walker

Jan A Lauber

Jorge P Fernandez

Disclosed is a method and apparatus for generating an image from a sample. The apparatus includes a charged particle beam generator arranged to generate and control a charged particle beam substantially towards a portion of the sample and a detector arranged to detect charged particles originating from the sample portion to allow generation of an image from the detected charged particles. The apparatus further includes a measurement device arranged to measure a characteristic of the sample portion to obtain a surface voltage value of the sample portion that is exposed to the charged particle beam. For example, the measurement device is an electrostatic voltmeter positioned to obtain a surface voltage value of the exposed sample portion. A charged particle beam is directed substantially towards a portion of the sample under a first set of operating conditions. A surface charge value of the sample portion is obtained under the first set of operating conditions. It is then determined whether an optimum set of operating conditions associated with a predetermined surface charge value have been found. When the optimum conditions have not been found, the operating conditions are adjusted and the charged particle beam is directed substantially towards the sample portion. When the optimum conditions have been found, the charged particle beam is directed substantially towards the sample portion under the found optimum operating conditions.

In-situ probe for optimizing electron beam inspection and metrology based on surface potential

Simultaneous flooding and inspection for charge control in an electron beam inspection machine

Systems and methods for determining the height of a surface of a specimen, such as a surface of a semiconductor device wafer are provided. A system may be configured to generate a comparison signal that may used to alter a Z-axis fine height adjustment of the system. The system may include for example, a processing tool, a metrology tool, or an inspection tool that may be used in semiconductor device fabrication. In this manner, the system may be configured to maintain a constant working distance between the wafer surface and an optical column of the system. A system may include an off-axis dual beam symmetric height sensor due to mechanical constraints of the system. The dual beam symmetric height sensor may provide automatic focusing of the wafer with high precision by substantially eliminating wafer pattern-induced error in comparison signals generated by the system.

Dual beam symmetric height systems and methods

Growing community of inventors

Campbell, CA, United States of America

Jun Pei