Method for forming photovoltaic cells employing multinary semiconductor films
First Claim
1. A method for use in the manufacture of photovoltaic cells having a film of a Cu-ternary semiconductor compound made up of a plurality of constituent elements, comprising the steps of:
- magnetron sputtering at least two constituent elements of the Cu-ternary compound simultaneously onto a substrate in a first preselected proportion; and
subsequently magnetron sputtering said at least two constituent elements simultaneously onto the substrate in at least one other preselected proportion;
whereby a composite sputtered film of the Cu-ternary compound having a preselected concentration gradient of at least one of the constituent elements is produced on the substrate.
3 Assignments
0 Petitions
Accused Products
Abstract
At least two constituent elements of a semiconductor compound are deposited in varying proportions by magnetron sputtering to produce a film having a preselected concentration gradient of the constituent elements. The film can be heat treated during or after deposition to diffuse the constituent elements within the film and enhance growth of a desired film structure. The sputtering step may be performed using a planar magnetron having a plurality of continuous magnetically enhanced sputtering cathodes extending about a common axis. Each of the cathodes includes a source structure containing at least one of the constituent elements, and provision for applying electrical power to the source structure to sputter the constituent element at a controlled rate. If one of the elements is difficult to control in the deposition process, it can be sputtered from a cathode made up of a stable alloy of the element and another constituent of the film. For example, when the semiconductor compound is CuInSe2, two of the sputtering cathodes may comprise In2 Se3 and Cu2 Se, respectively, and a third optimal cathode comprises either Cu or In.
186 Citations
13 Claims
-
1. A method for use in the manufacture of photovoltaic cells having a film of a Cu-ternary semiconductor compound made up of a plurality of constituent elements, comprising the steps of:
-
magnetron sputtering at least two constituent elements of the Cu-ternary compound simultaneously onto a substrate in a first preselected proportion; and subsequently magnetron sputtering said at least two constituent elements simultaneously onto the substrate in at least one other preselected proportion; whereby a composite sputtered film of the Cu-ternary compound having a preselected concentration gradient of at least one of the constituent elements is produced on the substrate. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
Specification