Low-temperature MOCVD of chromium carbonitride coatings from tetrakis(diethylamido)chromium and pyrolysis mechanism of this single-source precursor
✍ Scribed by Francis Maury; Franco Ossola
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 220 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0268-2605
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✦ Synopsis
Amorphous chromium carbonitride coatings with a low nitrogen content (3-8 at%) were deposited by low-pressure MOCVD in the temperature range 573-793 K using Cr(NEt 2 ) 4 as single-source precursor. This poor nitrogen incorporation is in agreement with the trends predicted by thermochemical calculations. XPS data, resistivity measurements and annealing experiments suggest that the films grown at 573 K are contaminated by organic species due to incomplete elimination of the ligands. The films deposited at higher temperature crystallize upon annealing at 873 K to form an orthorhombic ternary chromium carbonitride phase. The major volatile by-products of the MOCVD reaction were analyzed by 1 H and 13 C NMR. Their amount and the quasi-equimolar EtN=CHMe/ HNEt 2 ratio suggest that most of the NEt 2 ligands are removed by a stepwise mechanism which probably occurs with other diethylamido complexes of transition metals when they are used as single-source precursors in MOCVD. The incorporation of the metalloid elements in the film is discussed in comparison with recent literature data.