Method and system for measuring threshold length
AssigneeLam Research Corporation
InventorsCangshan Xu, Yuexing Zhao
Life of this patent
Estimating the term…
Abstract
A method and system for measuring threshold length of a planarization process, and for comparing the planarization abilities of such processes. The method and system measure a thickness profile of a film on a blanket wafer, and from the thickness profile, a threshold length is calculated.
Claims36
A method for determining the threshold length of a planarization process, the method comprising:
- measuring a varying thickness of a film layer on a portion of a blanket wafer;
- calculating the threshold length based upon variations in the thickness of said portion of said blanket wafer.
A method for determining whether a planarization process is effective to planarize a wafer, comprising:
- calculating the threshold length of the planarization process;
- and
- comparing at least one feature length of a wafer to said calculated threshold length to determine whether the planarization process would be effective to planarize said wafer.
A method for comparing two planarization processes, the method comprising;
- determining the threshold length of a first planarization process using a blanket wafer;
- determining the threshold length of a second planarization process using a blanket wafer;
- and
- comparing the threshold length of said first planarization process to the threshold length of said second planarization process.
A method for comparing two planarization processes, the method comprising:
- determining the threshold length of a first planarization process using a blanket wafer;
- determining the planarization length of a second planarization process using a patterned wafer;
- and
- comparing the threshold length of said first planarization process to the planarization length of said second planarization process.
A system for measuring the threshold length of a planarization process, the system comprising:
- a blanket wafer thickness determinator, said blanket wafer thickness determinator adapted to measure a varying thickness of a film layer of a blanket wafer and to create a signal indicative of said varying thickness;
- and
- a threshold length calculator in communication with said blanket wafer thickness determinator and adapted to calculate a threshold length based upon said signal received from said blanket wafer thickness determinator.
Dependencies are inferred from the claim text.