Aerosol-assisted chemical vapor deposition (AACVD) of silver, palladium and metal alloy (Ag1−xPdx, Ag1−xCux and Pd1−xCux) Films
✍ Scribed by Dr. Chongying Xu; Prof. Mark J. Hampden-Smith; Prof. Toivo T. Kodas
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 380 KB
- Volume
- 6
- Category
- Article
- ISSN
- 0935-9648
No coin nor oath required. For personal study only.
✦ Synopsis
Thin metal films have a wide variety of applications ranging from interconnects in semiconductor device manufacture"] and optical tailoring of glass monoliths[21 to gaspermeable membranes in separations technology.[3 -51 Chemical vapor deposition (CVD) is an attractive method of depositing metal films for these applications because thin, conformal coatings on complex topography substrates are often necessary, and for some applications selective-area deposition is desirable.
As a result of the scientific interest and potential economic impact of these applications, there has been a great deal of effort invested into the design and synthesis of inorganic, metal-organic and organometallic compounds specifically as precursors for the CVD ofnietals. It is a significant synthetic challenge to prepare metal-containing compounds that exhibit high vapor pressures and also react on a heated substrate at low temperatures to form high-purity metal films. This subject has been reviewed in detail recentlyL6' and there are only a few systems where these criteria can be met. In many cases the metal-containing precursor exhibits insufficient volatility or thermal stability to enable metal deposition at useful rates or the films formed are contaminated (usually by C and/or 0 ) .
We and others"-'] have been exploring methods to circumvent the necessity for high precursor vapor pressures and high thermal stability necessary when precursors must be heated for long periods in conventional precursor delivery systems. For example, supercritical fluid transport (SFT) CVD has been used to deposit a variety of metal and metaloxide films, but requires that the precursors be soluble in common supercritical fluids such as C0, and N20. [9] Aerosol delivery enables a high transport rate of the precursor to the substrate but does not require high precursor vapor pressure or long-term thermal stability at elevated temperatures (> 60 "C) for the CVD of Cu
Instead, aerosol delivery requires that the precursor is soluble in a solvent that does not decompose on the substrate surface during deposition of the metal film. The CVD of low-resis-