Controlling the dopant profile for SRH suppression at low current densities in λ ≈ 1330nm GaInAsP light-emitting diodes
Abstract
The quantum efficiency of double hetero-junction light-emitting diodes (LEDs) can be significantly enhanced at low current density by tailoring the spatial profile of dopants to suppress Shockley-Read-Hall (SRH) recombination. To demonstrate this effect we model, design, grow, fabricate, and test a GaInAsP LED (λ ≈ 1330nm) with an unconventional dopant profile. Compared against that of our control design, which is a conventional n+-n-p+ double hetero-junction LED, the dopant profile near the n-p+ hetero-structure of the new design displaces the built-in electric field in such a way as to suppress the J02 space charge recombination current. The design principle generalizes to other material systems and could be applicable to efforts to observe and exploit electro-luminescent refrigeration at practical power densities.