Oxide formation in a plasma process

摘要

A method of making a semiconductor structure is provided. The method includes forming a tunneling layer overlying a first channel connecting a source and a drain. A charge storage layer is formed overlying the tunneling layer, the charge storage layer comprises forming a substantially trap free first layer over the tunneling layer, and forming a trap dense second layer over the first layer. Finally, a blocking structure is formed on the charge storage layer by plasma oxidation. A thickness of the charge storage layer is reduced through oxidation of a portion of the charge storage layer during the formation of the blocking structure. Other embodiments are also described.

主权项

1. A method comprising:
forming a tunneling layer overlying a first channel connecting a source and a drain, wherein the first channel comprises a first silicon nanowire; forming a charge storage layer overlying the tunneling layer, the charge storage layer comprises forming a substantially trap free first layer over the tunneling layer, and forming a trap dense second layer over the first layer; forming a blocking structure on the charge storage layer by plasma oxidation, wherein a thickness of the charge storage layer is reduced through the plasma oxidation of a portion of the charge storage layer during forming the blocking structure; removing at least a portion of the blocking structure; measuring the thickness of the charge storage layer, and if a measured thickness exceeds a predetermined thickness, repeating the forming and removing of the blocking structure to further reduce the thickness of the charge storage layer; and if the measured thickness is less than the predetermined thickness, forming a final blocking structure on the charge storage layer, wherein forming the tunneling layer, the charge storage layer, and the blocking structure comprises forming the tunneling layer, the charge storage layer, and the blocking structure surrounding the first silicon nanowire to provide a gate all-around (GAA) architecture.