초록 ▼

An improved thin-film, large area solar cell, and methods for forming the same, having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n type heterojunction formed of: (i) a first semiconductor layer comprising a photovoltaic active

An improved thin-film, large area solar cell, and methods for forming the same, having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n type heterojunction formed of: (i) a first semiconductor layer comprising a photovoltaic active material selected from the class of I-III-VI2 chalcopyrite ternary materials which is vacuum deposited in a thin “composition-graded”layer ranging from on the order of about 2.5 microns to about 5.0 microns (2.5mm

대표청구항 ▼

In a method of forming a photovoltaic light-to-electrical energy transducer of the type including a thin-film A-B-type heterojunction where “A”and “B”are selected from the group of semiconductor materials consisting of: ________________________________ - A and B ________________________________ (i)

In a method of forming a photovoltaic light-to-electrical energy transducer of the type including a thin-film A-B-type heterojunction where “A”and “B”are selected from the group of semiconductor materials consisting of: ________________________________ - A and B ________________________________ (i) a p-type ternary material and an n-type material; (ii) an n-type ternary material and a p-type material; (iii) an n-type material and a p-type ternary material; (iv) a p-type material and an n-type ternary material; ________________________________ and wherein the transducer includes a substrate, a first contact deposited on the substrate, a first semiconductor layer formed of A-type material deposited on the first contact, a second semiconductor layer formed of B-type material deposited on the first semiconductor layer and defining therewith the thin-film A-B-type heterojunction, and a second contact deposited on the second semiconductor layer, the improvement comprising a method wherein: (a) the one of the first and second semiconductor layers formed of a ternary semiconductor material is formed by simultaneous elemental evaporation of the ternary semiconductor material to form a semiconductor layer having two composition graded regions sequentially formed one upon the other with one region having a first preselected ratio of two of the elements in the ternary semiconductor material so as to form a low resistivity semiconductor region and the other of the regions having a different preselected ratio of the same two elements so as to form a high resistivity transient semiconductor region and with the two regions defining a transient homojunction; and, (b) the other of the first and second semiconductor layers is formed by deposition of a semiconductor material in face-to-face contact with respect to the high resistivity transient semiconductor region of the transient homojunction so as to permit the high resistivity transient semiconductor region to evolve through elemental interdiffusion into a region of relatively high resistivity semiconductor material of the same type as the low resistivity region formed in step (a) to thereby form a thin-film A-B-type heterojunction photovoltaic light-to-electrical energy transducer. The product produced by the method set forth in claims 1, 2, 3, 4 or 5.