| 摘要 |
PROBLEM TO BE SOLVED: To provide good high-speed characteristics, good selectivity against base material, and low damage characteristics, by etching a silicon compound layer on a substrate with an etching gas comprising a saturated fluoro carbon compound comprising an annular part at least at a part of molecular structure while the substrate to be etched is controlled for cooling. SOLUTION: Related to a saturated fluoro carbon compound c-CnF2n comprising an annular part at a part of molecular structure, the number of fluorine atoms is less by two for a single molecule compared to a straight chain saturated fluoro carbon compound CnF2n+2 if the number of carbons is equal. So, C/F ratio of etching reaction system is lowered with no extra additive gas. A cooling piping of a reactive ion etching device is set on an incorporated wafer placement electrode, a coolant is supplied to the cooling piping from a cooling device for circulation, so that the temperature of wafer during etching is controlled to 50 deg.C or below. Thus, fast etching is possible with high selectivity, high anisotropism, and low damage characteristics. |
