Dry texturing of solar cells

Patent · Sat Jan 01 00:00:00 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, Kansas City, MO (United States)
• 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

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