Applied Materials, Inc.

Laksh Karuppiah

Boguslaw A Swedek

Dominic J Benvegnu

Feng Quan Liu

Kun Xu

Wen-Chiang Tu

Yuchun Wang

During polishing of a first substrate at a first polishing station, a sequence of measurements by a first in-situ monitoring system is monitored to determining a first time at which the first sequence exhibits a first predefined feature indicating a predetermined thickness of an overlying layer, and during polishing of the first substrate at a second polishing station, a sequence of measurements by a second in-situ monitoring system is monitored to determine a second time indicating clearance of the overlying layer and exposure of the underlying layer. The first time is used to calculate a first adjusted polishing pressure for a second substrate at the first polishing station, and the second time is used to calculate a second adjusted polishing pressure for the second substrate at the second polishing station.

Feedback of layer thickness timing and clearance timing for polishing control

In polishing a substrate having a layer of GST disposed over an underlying layer, during polishing, a non-polarized light beam is directed onto the layer of GST. The non-polarized light beam reflects from the first substrate to generate a reflected light beam having an infra-red component. A sequence of measurements of intensity of the infra-red component of the reflected light beam are generated, and, in a processor, a time at which the sequence of measurements exhibits a predefined feature is determined.

GST film thickness monitoring

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San Jose, CA, United States of America

Laksh Karuppiah