| 摘要 |
PROBLEM TO BE SOLVED: To provide an SiGe etch-stop material system on a monocrystalline silicon substrate useful for aqueous anisotropic etchants. SOLUTION: The SiGe etch-stop material system comprises a relaxed buffer layer graded up to Si<SB>1-x</SB>Ge<SB>x</SB>and a relaxed uniform etch-stop layer of the Si<SB>1-y</SB>Ge<SB>y</SB>, and it is preferable that x is equal to or smaller than 0.17 and y is equal to or greater than 0.3. The buffer layer has a linearly-changing composition with respect to thickness, from pure silicon at a substrate/buffer interface to a composition of germanium, and also has a chemical impurity substance. There is a strategic jump in germanium and concentration from the buffer side of the interface to the etch-stop material, such that the etch-stop layer is considerably more resistant to the etchant. COPYRIGHT: (C)2006,JPO&NCIPI
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