Back to results
US 5,961,877 AGranted
Wet chemical etchants
OwnerMcDonald Robinson, Richard C. Westhoff +2inventors
InventorsMcDonald Robinson, Richard C. Westhoff, Charles E. Hunt, Li Ling
Life of this patent
Estimating the term…
Abstract
Silicon-germanium-based compositions comprising silicon, germanium, and carbon (i.e., Si--Ge--C), methods for growing Si--Ge--C epitaxial layer(s) on a substrate, etchants especially suitable for Si--Ge--C etch-stops, and novel methods of use for Si--Ge--C compositions are provided. In particular, the invention relates to Si--Ge--C compositions, especially for use as etch-stops and related processes and etchants useful for microelectronic and nanotechnology fabrication.
Claims7
A wet chemical etchant, comprising:
- 3.5-15.8 mole percent of HF;
- 0.2-9.7 mole percent of HNO.sub.3 ;
- 34.8-82.6 mole percent of CH.sub.3 COOH;
- 12.3-46.5 mole percent of H.sub.2 O;
- and
- wherein the molecular ratio of HNO.sub.3 to HF is less than about 0.78.
3 more elements
A wet chemical etchant, comprising:
- 6.2-8.2 mole percent of HF;
- 0.3-6.9 mole percent of HNO.sub.3 ;
- 53.8-71.1 mole percent of CH.sub.3 COOH;
- 20.4-33.1 mole percent of H.sub.2 O;
- and
- wherein the molecular ratio of HNO.sub.3 to HF is less than about 0.78.
3 more elements
Dependencies are inferred from the claim text.