A method of epitaxially growing, preferably, a III - V compound semiconductor onto a substrate by forming a gaseous stream of (1) a gaseous mixture formed by a reaction of hydrogen halide (or water vapor) and a group III element and (2) at least one group V element; disposing a III - V compound semiconductor or a constituting element of a III - V compound semiconductor in a region held at a high temperature upstream of the substrate; reacting the gaseous stream, particularly unreacted hydrogen halide (or unreacted water vapor) with the disposed material and passing the thus reacted gaseous stream into contact with the substrate to deposite the III - V compound semiconductor on its surface. The substrate is maintained at a lower temperature than the disposed material. This process is similarly applied to mixed crystals as well as compound semiconductor layers of other groups.

An epitaxially grown high resistivity crystalline layer of gallium arsenide is produced in a reactor vessel with a predetermined amount of carbon dioxide introduced during growth of the high resistivity gallium arsenide (GaAs) crystalline layer to provide carbon as a dopant. Thus, a plurality of carbon atoms is provided in the crystal, such carbon atoms having electrons at energy levels between a valance energy band and a conduction energy band of the GaAs crystal. With these energy levels, the carbon atoms are substantially ionized at room temperature by accepting a plurality of electrons from the valance band of the GaAs. The presence of these carbon ions in the crystal compensates for a stoichiometric defect which occurs during epitaxial growth of the GaAs crystalline layer. This results in a high resistivity layer which provides a buffer layer between a GaAs substrate and an active GaAs layer. Further, by introducing carbon in the form of carbon dioxide, oxygen released during reduction of the carbon dioxide by reacting the carbon dioxide with hydrogen during the doping of the GaAs produces water. The water reduces the concentration of unwanted silicon oxide material generally introduced by the reactor vessel and contaminants and which is associated with unwanted background donor doping of the GaAs. By reducing the concentration of silicon oxide, the concentration of stoichiometric defects becomes the principle donor source, thus enabling optimum compensation thereof with carbon doping.

A method of forming and epitaxially depositing III-V compound crystals which comprises interacting two gaseous mixtures in the absence of oxidizing gas and hydrogen carrier gas, one mixture being formed by contacting a stream of an inert carrier gas with a gaseous trihalide of a Group III element and thereafter contacting that mixture with the same Group III element, the second mixture being formed by contacting a stream of an inert carrier gas with a Group V element or a volatile Group V compound.

A layer of a compound semiconductor having good quality is formed by disposing a substrate in an epitaxial growth layer, feeding a second reactant gas through a guide member extending from the downstream side to the upstream side of the flow of a first reactant gas, mixing the first reactant gas and second reactant gas, and supplying the resultant gaseous mixture of the first and second reactant gases onto the substrate.

Epitaxial deposition apparatus includes a bell jar disposed within a furnace and having therein a closed annulus adapted to contain material to be vaporized when heated. First tubular means delivers gaseous reactant to the annulus and second tubular means delivers the reaction product, of the vaporized material and gaseous reactant, to a top portion of the bell jar. Means deliver a second gaseous reactant to said top portion. Means support a substrate at an intermediate portion of the bell jar.