Compositions of matter, and methods of removing silicon dioxide

摘要

Some embodiments include methods of removing silicon dioxide in which the silicon dioxide is exposed to a mixture that includes activated hydrogen and at least one primary, secondary, tertiary or quaternary ammonium halide. The mixture may also include one or more of thallium, BX3 and PQ3, where X and Q are halides. Some embodiments include methods of selectively etching undoped silicon dioxide relative to doped silicon dioxide, in which thallium is incorporated into the doped silicon dioxide prior to the etching. Some embodiments include compositions of matter containing silicon dioxide doped with thallium to a concentration of from about 1 weight % to about 10 weight %.

主权项

1. A semiconductor construction comprising:
a semiconductor substrate; a pair of silicon-dioxide materials over the semiconductor substrate and directly laterally adjacent one another, each of the pair of silicon-dioxide materials being in direct physical contact with the semiconductor substrate; one of the silicon dioxide-containing materials being undoped and the other of the silicon dioxide-containing materials containing silicon dioxide and thallium; and wherein the pair of laterally adjacent silicon dioxide materials are retained in the final semiconductor construction.