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Engineering topics

Ludowise, M. J.

Publications and source records attributed to Ludowise, M. J..

Development of a 30 percent efficient 3-junction monolithic cascade solar cell

The individual subcells of the 3-junction monolithic cascade concentrator cell are grown lattice mismatched with respect to each other, if appropriate grading layers are inserted between the mismatched layers. Under these conditions, negligible degradation of the properties of either underlying or overlying material results, and high-efficiency subcells are produced by this technique.

Lewis, C. R.↗

OM-VPE growth of Mg-doped GaAs

The epitaxial growth of Mg-doped GaAs by the organometallic vapor phase epitaxial process (OM-VPE) has been achieved for the first time. The doping is controllable over a wide range of input fluxes of bis (cyclopentadienyl) magnesium, (C5H5)2Mg, the organometallic precursor to Mg.

Lewis, C. R.↗

Progress toward cascade cells made by OM-VPE

Organometallic Vapor Phase Epitaxy (COM-VPE) was used to make a sophisticated monolithic cascade cell, with a peak AMO efficiency of 16.6%, not corrected for 14% grid coverage. The cell has 9 epitaxial layers. The top cell is 1.35 microns thick with a 0.1 micron thich emitter. Both cells are heteroface n-p structures. The cascade cell uses metal interconnects. Details of growth and processing are described.

Borden, P. G.↗

Use of column V alkyls in organometallic vapor phase epitaxy (OMVPE)

The use of the column V-trialkyls trimethylarsenic (TMAs) and trimethylantimony (TMSb) for the organometallic vapor phase epitaxy (OM-VPE) of III-V compound semiconductors is reviewed. A general discussion of the interaction chemistry of common Group III and Group V reactants is presented. The practical application of TMSb and TMAs for OM-VPE is demonstrated using the growth of GaSb, GaAs(1-y)Sb(y), Al(x)Ga(1-x)Sb, and Ga(1-x)In(x)As as examples.

Ludowise, M. J.↗