摘要 |
The subject invention is directed to a process for etching a semiconductor device to form a predetermined etched pattern therein. The semiconductor device which is provided herein typically has a plurality of layers. At least one of these layers comprises a metal-containing material having a metal content of at least about 80% by weight. Etching the semiconductor device with an etchant material forms a predetermined etched pattern therein. This pattern includes the formation of horizontal and upright sidewalls in the etched layers which comprise the metal-containing material. Thus, each of the upright sidewalls has a profile which is either substantially vertically sloped or is positively sloped. This is the case even though the chemical etchant composition, when employed by itself to etch the above-described metal-containing layers, forms sidewall profiles which are substantially negatively sloped configuration. The etchant material employed herein comprises a chemical etchant composition and a coating composition. In one preferred form of this invention the coating composition comprises water vapor or a gaseous oxide of nitrogen, particularly N2O, and a silicon-containing compound, respectively. The etchant material is in a substantially gas phase during the etching of the semiconductor device and deposits a protective film on the upright sidewalls of the etched semiconductor device. The silicon-containing compound typically comprises a silicon tetrahalide, preferably comprising SiCl4, SiBr4, or SiF4. However, the most preferred compound being SiBr4.
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