Abstract: A method for fabricating a compound semiconductor epitaxial wafer having a uniform epitaxial layer-thickness distribution independently of positions of compound semiconductor wafers placed within a reaction furnace (19), and a vapor phase growth apparatus for implementing the method. A group III source gas (13) is flowed from a gas inlet (14) of the reaction furnace (19) to a gas outlet (16) thereof, whereas a group V source gas (15) is supplied as dispersedly from a plurality of groups of gas discharge ports (18a, 18b, 18c) provided in a flow direction of the group III source gas (13).

Abstract: A method for manufacturing compound semiconductor epitaxial wafer allowing sharp changes in alloy composition and growth of high-quality epitaxial layers.

Abstract: At the time of forming an alloy composition gradient layer 4 of gallium arsenide phosphide GaAs.sub.x P.sub.1-x having an arsenic alloy composition x changed in such a range as not to exceed a predetermined alloy composition a with an increase of a layer thickness d between a GaP layer 3 and a composition constant layer 5 of gallium arsenide phosphide GaAs.sub.a P.sub.1-a having the predetermined alloy composition a to be grown above the GaP layer; the alloy composition x is abruptly ascended as in composition ascending zones C11 to C13 with the ascended thickness d of an epitaxial layer and then descended as in crystal stabilizing zones S11 to S13 in such a range as not to cancel the previous ascent amount. One or more combinations of such ascent and descent in the alloy composition are repeated to form as distributed in the alloy composition gradient layer 4, and then the alloy composition x is ascended to the predetermined alloy composition a.

Abstract: A GaAsP epitaxial wafer 10 which has a GaAs.sub.1-x P.sub.x (0.45<x<1) constant nitrogen concentration layer 6 formed by doping a constant composition layer with nitrogen wherein the constant nitrogen concentration layer 6 has the following upper and lower limits of nitrogen concentration:Upper limit: N=(6.25x-1.125).times.10.sup.18 cm.sup.-3Lower limit: N=(5x-1.5).times.10.sup.18 cm.sup.

Abstract: A compound semiconductor epitaxial wafer added with nitrogen to provide a high luminous efficiency. Epitaxial layers are grown on a single crystalline substrate 4 made of gallium phosphide or gallium arsenide to form a compound semiconductor epitaxial wafer EW. The epitaxial layers include at least an nitrogen-added gallium phosphide arsenide mixed crystalline epitaxial layer having an n-type carrier concentration descending gradually toward the uppermost surface of the grown layer in a continuous or stepwise manner before p-type impurity is diffused, and contain an intermediate layer 83 with an n-type carrier concentration of 4.times.10.sup.14 /cm.sup.3 or more and less than 3.5.times.10.sup.15 /cm.sup.3, and a surface layer 84 having an n-type carrier concentration equals to or lower than that for the intermediate layer 83.

Abstract: A method for a vapor-phase growth of a GaAs.sub.1-x P.sub.x epitaxial layer having a uniform thickness is disclosed. This method allows the GaAs.sub.1-x P.sub.x epitaxial layer (wherein x stands for an alloy composition satisfying the expression, 0.ltoreq.x.ltoreq.1) to be formed on a plurality of semiconductor single crystal substrates 1 by setting the semiconductor single crystal substrates 1 in place on a wafer holder 16 disposed inside a vapor-phase growth apparatus 30 in an amount of not less than 70% as the covering ratio of the total surface area of the substrates to the surface area of the wafer holder 16.

Abstract: A compound semiconductor single crystal which has an Si concentration of not more than 1.times.10.sup.17 atoms/cm.sup.3 and/or an O concentration of not more than 7.times.10.sup.16 atoms/cm.sup.3 is particularly suitable for use as substrate for epitaxial deposition of a high luminance light-emitting device which emits green light.