Plasma-based method for delayering of circuits

Patent Number: 11664238
Issued: 5/30/2023
Official Filing: View the Complete Patent
Abstract: The present invention relates to methods of delayering a semiconductor integrated circuit die or wafer. In at least one aspect, the method includes exposing a die or wafer to plasma of an etching gas and detecting exposure of one or more metal layers within the die. In one aspect of the invention, the plasma of the etching gas is non-selective and removes all materials in a layer at about the same rate. In another aspect of the invention, two different plasmas of corresponding etching gases are employed with each plasma of the etching gas being selective, thus necessitating the sequential use of both plasmas of corresponding etching gases to remove all materials in a layer.
Filed: 7/29/2020
Government Interests: STATEMENT OF GOVERNMENT INTEREST This invention was made with Government support under Contract No. DE-NA0003525 awarded by the United States Department of Energy/National Nuclear Security Administration. The Government has certain rights in the invention.