Use of Vacuum Chucks to Hold a Wafer or Wafer Sub-Stack

摘要

Techniques are described for holding a wafer or wafer sub-stack to facilitate further processing of the wafer of sub-stack. In some implementations, a wafer or wafer sub-stack is held by a vacuum chuck in a manner that can help reduce bending of the wafer or wafer sub-stack.

主权项

1. A method of forming features on a wafer using a replication process, the method comprising:
placing a wafer on a vacuum chuck, wherein a first surface of the wafer that faces the vacuum chuck includes features that project toward the vacuum chuck, and wherein the vacuum chuck includes a central recessed surface on which a silicone mat is disposed; applying pressure to a second surface of the wafer on a side of the wafer opposite its first surface such that the features of the wafer on its first surface are in contact with the silicone mat, and wherein part of the first surface of the wafer near its periphery is in contact with an elevated section of the vacuum chuck that includes a vacuum channel; generating a vacuum using the vacuum channel so as to hold the wafer to the vacuum chuck; and subsequently bringing a replication tool into contact with the second surface of the wafer to form features on the second surface of the wafer using a replication process.