Apparatus for forming thin-film heterojunction solar cells employing materials selected from the class of I-III-VI.sub.2 chalcopyrite compounds

Patent · Fri Dec 31 23:00:00 EST 1982

OSTI ID:864614

Mickelsen, Reid A ^[1]; Chen, Wen S ^[2]

---

1. Bellevue, WA
2. Seattle, WA

Apparatus for forming thin-film, large area solar cells 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-VI.sub.2 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 (.congruent.2.5 .mu.m to .congruent.5.0 .mu.m) and wherein the lower region of the photovoltaic active material preferably comprises a low resistivity region of p-type semiconductor material having a superimposed region of relatively high resistivity, transient n-type semiconductor material defining a transient p-n homojunction; and (ii), a second semiconductor layer comprising a low resistivity n-type semiconductor material wherein interdiffusion (a) between the elemental constituents of the two discrete juxtaposed regions of the first semiconductor layer defining a transient p-n homojunction layer, and (b) between the transient n-type material in the first semiconductor layer and the second n-type semiconductor layer, causes the transient n-type material in the first semiconductor layer to evolve into p-type material, thereby defining a thin layer heterojunction device characterized by the absence of voids, vacancies and nodules which tend to reduce the energy conversion efficiency of the system.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO
• DOE Contract Number: EG-77-C-01-4042
• Assignee: Boeing Company (Seattle, WA)
• Patent Number(s): US 4392451
• OSTI ID: 864614
• Country of Publication: United States
• Language: English

Related Subjects

/118/148/
absence
active
active material
apparatus
causes
cell
cell comprises
cells
cells employing
chalcopyrite
chalcopyrite ternary
characterized
composition-graded
compounds
comprises
comprising
congruent
constituents
conversion
conversion efficiency
defining
deposited
device
discrete
discrete juxtaposed
efficiency
electrical energy
elemental
elemental constituents
employing
energy
energy conversion
evolve
film heterojunction
formed
forming
forming thin-film
heterojunction
heterojunction formed
heterojunction solar
homojunction
homojunction layer
i-iii-vi
ii
interdiffusion
junction device
junction solar
juxtaposed
juxtaposed regions
layer
layer comprising
layer defining
layer ranging
light-to-electrical
light-to-electrical energy
material
material defining
material preferably
material selected
materials
materials selected
microns
n-type
n-type material
n-type semiconductor
nodules
p-n
p-n homojunction
p-n-type
p-type
p-type material
p-type semiconductor
photovoltaic
photovoltaic active
preferably
preferably comprise
preferably comprises
ranging
reduce
region
regions
relatively
resistivity
resistivity n-type
resistivity region
selected
semiconductor
semiconductor layer
semiconductor material
solar
solar cell
solar cells
superimposed
superimposed region
tend
ternary
ternary materials
thin-film
thin-film heterojunction
transient
transient n-type
transient p-n
type heterojunction
type material
type semiconductor
vacancies
vacuum
vacuum deposited
voids