Minority carrier diffusion length, lifetime and mobility in p-type GaAs and GaInAs

Abstract

Minority carrier diffusion lengths and lifetimes were determined for p-type Ga(1-x)InxAs with an In-content of 0 ≤ x ≤ 0.53 by cathodoluminescence and time-resolved photoluminescence measurements respectively under low injection conditions; the resulting minority carrier mobilities are also reported. Highly p-doped samples (3 × 1018 cm−3) demonstrate a constant minority carrier diffusion length of (5.0 ± 0.7) μm and a constant lifetime of (3.7 ± 0.7) ns for an In-content up to 21%. Lower doped samples (3 × 1017 cm−3), on the other hand, show an increase in minority carrier diffusion length and lifetime with In-content from (6.3 ± 0.2) μm and (6.2 ± 0.5) ns respectively for GaAs to (14 ± 2) μm and (24.4 ± 0.5) ns respectively for Ga0.79In0.21As. Increasing the In-content to 53% results in a drop in the minority carrier diffusion length independently of the p-doping concentration .This is interpreted as a change in the energy of the Shockley-Read-Hall trap levels within the bandgap as a function of indium concentration

Modeling and simulation of high-efficiency GaAs PIN solar cells

“…The diffusion of minority carriers along the junction surface was neglected. The calculated EW value was found to be much smaller than the surface DL reported in early studies [23][24][25][26][27][28]. It was discovered that the SR current is due to the drift diffusion of carriers inside the depletion region and this current is dominant at low bias.…”

Оптимизация толщины слоя In-=SUB=-0.3-=/SUB=-Ga-=SUB=-0.7-=/SUB=-As в трехкаскадном In-=SUB=-0.3-=/SUB=-Ga-=SUB=-0.7-=/SUB=-As/GaAs/In-=SUB=-0.5-=/SUB=-Ga-=SUB=-0.5-=/SUB=-P солнечном элементе

“…Однако при увеличении времени жизни ННЗ выигрыш от применения оптимальной толщины начинает резко увеличиваться и при времени жизни ННЗ, равном 26.7 нс, начинает выходить " на полку". Возможность создания структур данного типа с величинами времен жизни ННЗ ∼ 25 нс показана, например, в работе [8]. Как видно из графика, выигрыш от применения оптимальной толщины при данном значении времени жизни ННЗ составляет 0.5%.…”

A Cathodoluminescence Study on the Diffusion Length in AlGaInP/InGaP/AlInP Solar Cell Heterostructures

“…Cross-sectional electron beam induced current (EBIC) and transport imaging in a scanning electron microscope are two techniques applied to measure the minority carrier diffusion length. However, the electric fields and surface recombination are the challenges of the EBIC method [4,5], while a 2D-CCD camera is necessary for the transport imaging technique [6,7]. Cathodoluminescence (CL) has been also applied to measure the minority carrier diffusion length in semiconductors [8].…”