Selective interhalogen etching of tantalum compounds and other semiconductor materials
- 15 April 1985
- journal article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 46 (8) , 794-796
- https://doi.org/10.1063/1.95886
Abstract
We find that gaseous ClF3 is an effective and selective etchant for a variety of transition metals and metal compounds. Kinetics were studied for etching α-Ta (13–16 atom % N), Ta2N, and Ta2O5 in this gas, as a function of temperature and pressure, to provide effective activation energies of 4.0, 4.4, 7.7 kcal/mole, respectively. Relative etch rates measured in CF4/O2 and NF3 plasmas indicate that ClF3 gaseous etching has more than an order of magnitude better selectivity for nonoxidic metal compounds over the corresponding oxide. At 100 °C, selectivity for etching α-Ta or Ta2N over Ta2O5 is more than 160:1. Other materials used in semiconductor manufacture, such as SixNy, W, TaSi2, and photoresist, were also briefly surveyed and the results suggest ClF3 holds promise for isotropic etching applications that require high selectivity.Keywords
This publication has 6 references indexed in Scilit:
- Plasmaless dry etching of silicon with fluorine-containing compoundsJournal of Applied Physics, 1984
- Comparison of XeF2 and F-atom reactions with Si and SiO2Applied Physics Letters, 1984
- Crystallographic etching of GaAs with bromine and chlorine plasmasJournal of Applied Physics, 1983
- The reaction of fluorine atoms with siliconJournal of Applied Physics, 1981
- Mechanisms of radical production in radiofrequency discharges of CF3Cl, CF3Br, and certain other plasma etchants: Spectrum of a transient speciesJournal of Applied Physics, 1980
- The etching of silicon with XeF2 vaporApplied Physics Letters, 1979