Patent ID: 7189332

Claim:
A method for etching a sample comprising: providing a sample to be etched to an etching chamber; providing a vapor phase etchant through the chamber to etch the sample, the vapor phase etchant capable of etching the sample in a non-energized state, wherein the etchant is selected from the group consisting of noble gas fluorides and halogen fluorides; wherein the etchant is mixed with a non-etchant gaseous additive; wherein a partial pressure of said etchant gas in said gas mixture is at least about 0.1 mbar, and the molar ratio of said non-etchant gaseous additive to said etchant gas is from about 1:1 to about 500:1; passing the vapor phase etchant and/or etching products into and out of the etching chamber when etching the sample; monitoring the vapor phase etchant and/or an etching product within or coming from the etching chamber, determining the end point of the etch based on the monitoring of the gas in or from the etching chamber; wherein the sample comprises a silicon material that is part of a silicon portion that is etched relative to a non-silicon portion of the sample, said non-silicon portion consisting of a member selected from the group consisting of a non-silicon metal, a compound of a non-silicon metal, and a silicon-containing compound in which silicon is bonded to a non-silicon element; and wherein both said silicon portion and said non-silicon portion are exposed to the etchant gas.