Inverted Metamorphic Multijunction (IMM) Cell Processing Instructions

Technical Report · Wed Feb 01 00:00:00 EST 2012

DOI:https://doi.org/10.2172/1036035· OSTI ID:1036035

Duda, Anna ^[1]; Ward, Scott ^[1]; Young, Michelle ^[1]

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1. National Renewable Energy Laboratory (NREL), Golden, CO (United States)

This technical report details the processing schedule used to fabricate Inverted Metamorphic Multijunction (IMM) concentrator solar cells at The National Renewable Energy Laboratory (NREL). These devices are used as experimental test structures to support the research at NREL that is focused on increasing the efficiency of photovoltaic power conversion. They are not intended to be devicessuitable for deployment in working concentrator systems primarily because of heat sinking issues. The process schedule was developed to be compatible with small sample sizes and to afford relatively rapid turn-around times, in support of research efforts. The report describes the use of electro deposition of gold for both the back and front contacts. Electro-deposition is used because of itsrapid turn around time and because it is a benign metallization technique that is seldom responsible for damage to the semiconductors. The layer transfer technique is detailed including the use of a commercially available adhesive and the etching away of the parent gallium arsenide substrate. Photolithography is used to define front contact grids as well as the mesa area of the cell. Finally,the selective wet chemical etchant system is introduced and its use to reveal the back contact is described.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Office of Renewable Energy. Solar Energy Technologies Office
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 1036035
• Report Number(s): NREL/TP--5200-54049
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
42 ENGINEERING
ADHESIVES
CONCENTRATOR SOLAR CELLS
CONCENTRATORS
DEPOSITION
EFFICIENCY
ETCHING
GALLIUM ARSENIDES
GOLD
IMM
IMM cell processing
NATIONAL RENEWABLE ENERGY LABORATORY
PROCESSING
SCHEDULES
gallium arsenide (GaAs)
gallium indium phosphide (GaInP)
inverted metamorphic multijunction