Characterisation of Mn-doped and nominally pure LPE Ga_xIn_1-xAs_yP_1-y(y=2.1x) between y=0 and y=1 using photoluminescence and electrical measurements

Abstract

Photoluminescence (PL) and electrical measurements have been made on a series of p-type, Mn-doped layers of GaxIn1-xAsyP1-y (y=2.1x) grown by liquid phase epitaxy on InP substrates and of a similar series of nominally pure crystals used as control samples. For small y, the Mn-doped samples shown an intense Mn-related PL band with a zero-phonon structure at 1.185 eV (4K) for the y=0 (InP) sample. This locates the Mn-acceptor level at 230 meV above the valence band edge. The PL band can be followed up to y=0.40 and the Mn-acceptor energy EA is estimated to vary as (230-185y) meV. For larger y, a broad, though strong, PL is observed on the low energy side of the near-band-edge lines. At these higher y values, electrical measurements have been used to determine EA, giving EA=49 meV for y=0.93 and 0.10 eV for y=0.70, in fairly good agreement with linear extrapolation of the PL data. The low temperature PL of six undoped control samples (0.5<y<1) reveal two sharp PL lines at (1.02-0.33y) and (1.00-0.33y) eV of as yet unknown origin.

Improved values of the forward X-ray scattering factor for metallic aluminium

“…These values are to be compared with the square of the Thomson value, Z 2, where Z is the atomic number. Apart from small relativistic corrections (Smith, 1986(Smith, , 1987Wang, 1986), this is the limit of [f[ at high frequencies and equals 169 for aluminium. For spectral regions far from absorption edges, the present results forfl agree well with theoretical predictions.…”

Characterization of Mn-Doped in 1−x GaxAsyP1−y Grown By Lpee

“…Published data points [8,9] for Mn-doped quaternary are also included for comparison. The values of nobilities we have obtained are a little higher than the reported values for the layers grown by conventional LPE.…”

“…Mn was chosen as it has been found [8][9][10] to be a suitable p-type dopant for device applications, in quaternary alloys of compositions closer to the ternary In 5 3 Ga 47 As. The hole concentration and the hole mobility were investigated, in detail, to estimate the activation energy of the dopant, carrier compensation and the prevalent scattering mechanisms in the quaternary and are compared with the published data.…”