Altering proportions in vapor deposition process to form a mixed crystal graded energy gap

Claim 1

PROCESS FOR THE PRODUCTION AND DEPOSITION OF GRADED FORBIDDEN ENERGY GAP EPITAXIAL FILMS OF MIXED BINARY CRYSTALS COMPRISING ELEMENTS SELECTED FROM THE GROUP II ELEMENTS OF THE CLASS OF BERYLLIUM, ZINC, CADMIUM AND MERCURY, AND GROUP VI ELEMENTS OF THE CLASS OF SULFUR, SELENIUM AND TELLURIUM ONTO A SUBSTRATE MATERIAL SELECTED FROM THE CLASS CONSISTING OF III-V COMPOUNDS, I-VII COMPOUNDS, II-VI COMPOUNDS, GERMANIUM AND SILICON, WHICH COMPRISES REACTING IN THE VAPOR PHASE AT LEAST ONE VOLATILE COMPONENT OF THE CLASS OF ELEMENTS AND COMPOUNDS OF THE AFORESAID GROUP II ELEMENTS TOGETHER WITH AT LEAST ONE VOLATILE COMPONENT OF THE CLASS OF ELEMENTS AND COMPOUNDS OF THE AFORESAID GROUP VI ELEMENTS, PROVIDED THAT THE SUM OF THE GROUP II COMPONENTS AND GROUP VI COMPONENTS REACTED IS GREATER THAN TWO, IN THE PRESENCE OF HYDROGEN WHILE EXCLUDING OXIDIZING GASES AND CONTACTING THE RESULTING REACTION MIXTURE WITH SAID SUBSTRATE WHEREBY A PURIFIED SINGLE CRYSTAL FORM A MIXED BINARY CRYSTALS IS DEPOSITED FROM SAID REACTIONS MIXTURE AS AN EPITAXIAL FILM ON SAID SUBSTRATE, WHILE PROGRESSIVELY ALTERING THE RELATIVE PROPORTIONS OF THE TWO REACTANTS OF THE SAME GROUP AS THE DEPOSITION PROCEEDS.