Dry texturing of solar cells

Patent · Sat Jan 01 04:00:00 EST 1994

OSTI ID:869572

Sopori, Bhushan L ^[1]

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1. Denver, CO

A textured backside of a semiconductor device for increasing light scattering and absorption in a semiconductor substrate is accomplished by applying infrared radiation to the front side of a semiconductor substrate that has a metal layer deposited on its backside in a time-energy profile that first produces pits in the backside surface and then produces a thin, highly reflective, low resistivity, epitaxial alloy layer over the entire area of the interface between the semiconductor substrate and a metal contact layer. The time-energy profile includes ramping up to a first energy level and holding for a period of time to create the desired pit size and density and then rapidly increasing the energy to a second level in which the entire interface area is melted and alloyed quickly. After holding the second energy level for a sufficient time to develop the thin alloy layer over the entire interface area, the energy is ramped down to allow epitaxial crystal growth in the alloy layer. The result is a textured backside an optically reflective, low resistivity alloy interface between the semiconductor substrate and the metal electrical contact layer.

• Research Organization: MIDWEST RESEARCH INSTITUTE
• DOE Contract Number: AC02-83CH10093
• Assignee: Midwest Research Institute (Kansas City, MO)
• Patent Number(s): US 5358574
• OSTI ID: 869572
• Country of Publication: United States
• Language: English

Related Subjects

/438/136/
absorption
accomplished
allow
alloy
alloy layer
alloyed
applying
backside
backside surface
cells
contact
contact layer
create
crystal
crystal growth
density
deposited
desired
desired pit
device
dry
electrical
electrical contact
energy
energy level
entire
epitaxial
front
growth
highly
highly reflective
holding
increasing
infrared
infrared radiation
interface
layer
layer deposited
level
light
light scattering
melted
metal
metal contact
metal electric
metal electrical
metal layer
optically
period
pit
pit size
pits
produces
produces pits
profile
quickly
radiation
ramped
ramping
rapidly
reflective
resistivity
resistivity alloy
result
scattering
semiconductor
semiconductor device
semiconductor substrate
size
solar
solar cell
solar cells
substrate
sufficient
sufficient time
surface
textured
texturing
time
time-energy
time-energy profile