Optimization of annealing conditions of (GaIn)(NAs) for solar cell applications

Narrow band gap GaInNAsSb material grown by metal organic vapor phase epitaxy (MOVPE) for solar cell applications

“…Performance-related issues, such as low internal quantum efficiencies (IQEs) and photocurrent mismatch between individual cells, have been correlated to the N content ($ 2-3%) required to achieve a 1.0 eV band gap in GaInNAs material [10]. Post-growth thermal treatments improve the IQEs associated with these devices [18], but high background carbon concentrations, generally observed in MOVPE-grown material, have been correlated with these poor minority carrier diffusion lengths. Recently, it has been shown in MBE grown materials that the addition of Sb, in dilute amounts to strained GaInNAs, can improve the performance of quantum well (QW) lasers [9] as well as increase the IQE of bulk, lattice-matched material used in solar cells [10].…”

MOVPE growth of dilute nitride III/V semiconductors using all liquid metalorganic precursors

“…The present paper tries to reconcile this controversy by studying the N-incorporation in great detail by varying the temperature, the V/III-ratio, the V/V-ratio, the growth rate, the reactor pressure, the chemical composition as well as the strain-state of the Ga(NAs) and (GaIn)(NAs) films also for different N-precursor molecules. The optoelectronic properties of several samples discussed here are described in separate publications [46,47], as photoluminescence in dilute nitride materials is a complex function also of annealing conditions, which is not the topic of the present paper.…”

p- to n-type conductivity transition in 1.0 eV GaInNAs solar cells controlled by the V/III ratio

“…Some of them can be annealed by a thermal treatment, but others are stable to at least some extend. 8,9 Not all of the defects have been identified yet but there is evidence for the formation of As Gaantisites, 10,11 N interstitials, 9,12 N-N chain ordering, 13,14 or Ga-vacancies. [15][16][17] Especially, Ga-vacancy defects are known to be responsible for the relatively high ($10 16 cm…”