Therma-wave, Inc.

Keri Systems, Inc.

Dale Lindseth

Kenneth J Geiszler

Russel E Walker

Jon Kwong

Kenneth Alan Whiston

Mihail Mihaylov

A detector network for an optical metrology system includes an analog to digital converter for each photodetector or detector array. Each analog to digital converter is connected to provide digitally encoded output from its associated detector. Each analog to digital converter is also connected to a hub. The hub receives commands from a processor and distributes them to the analog to digital converters. The converters sample the output of their associated detectors and return the digitized results to the hub. In turn, the hub passes the digitized results to the processor for analysis.

Digital detector data communication in an optical metrology tool

The system and method herein provide a prealigner that has reduced sensitivity to distorting ambient light influences in the environment of a prealigner integrated in a metrology apparatus. A modulated signal is produced by a photo detector in response to modulated light that is partially shielded by wafer positioned in a gap between light source and detector. The pulsed signal is bandpass filtered and demodulated whereby only the difference between high- and low-levels of the pulsed signal are recognized. Flickering and DC components related to ambient light and other distorting operational influences are removed from the analysis unrecognized. Demodulation is synchronously accomplished together with a switching of the light source's power supply. For stable voltage levels of the power supply, a current source is buffered during off-intervals for a constant load on the current source. Also a power steering switch samples the buffers voltage level and takes it as switching condition for the next on-interval of the power supply. Preferably a switched capacitor building block is used as synchronizing element. A final analog output signal is prepared for sampling.

Wafer prealigner with phase sensitive detection

An object identification system and method detects the presence of a target object in a field of inspection and in one aspect of the invention, generates a first signal if the object is left in the field of inspection for more than a minimum threshold period of time. In a second aspect a second signal is generated if the object is introduced to the field of inspection more than a minimum threshold number of times (having been withdrawn from the field of inspection in the interim) within a minimum threshold period of time.

Electronic reader for reading a special characteristic of an object

A radio frequency identification system includes a transponder and a transponder reader. The transponder, responsive to an interrogation signal continuously transmitted by the transponder reader, generates a transponder signal modulated by an identification signal readable by the transponder reader. The identification signal includes a synchronization portion, a data portion, an output format identification portion, and an error detection portion. The output format identification portion is used by the reader to configure itself for communication with an attached controller. In another aspect of the invention, the transponder reader may be configured to read FSK as well as PSK encoded signals from the transponder.

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Hollister, CA, United States of America

Dale Lindseth