A multijunction, monolithic, photovoltaic (PV) cell and device (600) is provided for converting radiant energy to photocurrent and photovoltage with improved efficiency. The PV cell includes an array of subcells (602), i.e., active p/n junctions, grown on a compliant substrate, where the compliant substrate accommodates greater flexibility in matching lattice constants to adjacent semiconductor material. The lattice matched semiconductor materials are selected with appropriate band-gaps to efficiently create photovoltage from a larger portion of the solar spectrum. Subcell strings (601, 603) from multiple PV cells are voltage matched to provide high output PV devices. A light emitting cell and device is also provided having monolithically grown red-yellow and green emission subcells and a mechanically stacked blue emission subcell.
CONTRACTUAL ORIGIN OF THE INVENTION
 The United States Government has rights in this invention under Contract No. DE-AC36-99GO10337 between the United States Department of Energy and the National Renewable Energy Laboratory, a Division of the Midwest Research Institute.