OHMIC CONTACTS TO INP-BASED MATERIALS INDUCED BY MEANS OF RAPID THERMAL LOW-PRESSURE (METALLORGANIC) CHEMICAL VAPOR-DEPOSITION TECHNIQUE

A rapid-thermal-low-pressure-metallorganic-chemical-vapor-deposition (RT-LPMOCVD) technique was executed in order to deposit non-semiconductor thin layer materials, necessary for producing metal contact to InP-based microelectronic devices. Silicon dioxide (SiO2) films were deposited onto InP substrates in rapid thermal cycles, using O2 and 2% diluted SiH4 in Ar, with very fast growth kinetics and low activation energy. The SiO2 film exhibited excellent properties, such as refractivity index, density, internal stress, and wet p-etch rates. The SiO2 films were dry etched in a given pattern to allow for the formation of a small metal contact to the InP-based material, onto which the SiO2 layer was deposited. Subsequently, titanium-nitride (TiNx) thin films were deposited onto the InP substrate through rapid thermal deposition cycles, using a tetrakis (dimethylamido) titanium (DMATi) metallorganic liquid source as the precursor for the process, with fast kinetics. The deposited TiNx films had a stoichiometric structure and contained nitrogen and titanium in a ratio close to unity, but incorporated a large amount of carbon and oxygen. The film properties, such as resistivity (40-80-mu-OMEGA . mm) and stress (compressive; -0.5 to -2.0 X 10(9) dyne . cm-2), were studied in addition to an intensive investigation of its microstructure and morphology, and their performance as an ohmic contacts while deposited onto p - In0.53Ga0.47As material (Zn doped 1.2 x 10(18) cm-3).