Electrical characterization of InP/GaInP quantum dots by space charge spectroscopy
- 1 October 1998
- journal article
- research article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 84 (7) , 3747-3755
- https://doi.org/10.1063/1.368553
Abstract
An investigation of coherently grown InP quantum dots embedded in Ga 0.5 In 0.5 P by conventional space charge spectroscopy methods is reported. Deep level transient spectroscopy(DLTS) is used to obtain quantitative information on the electron emission from the dots. The applied field is found to significantly enhance the electron emission rates as seen by shifts in the peaks towards lower temperatures with increased field. Taking the field induced barrier lowering into account, the emission energy for the one electron ground state of the dot is determined as 240±10 meV. The correlation between the measured signal and the observed electron accumulation in capacitance–voltage measurements is clearly demonstrated. Further, studies of the electron emission when the average electron population in the dots was varied show that the emission energies are modified by the coulomb charging energy. Admittance measurements as a function of temperature, bias and frequency were also performed, and the results are qualitatively explained in terms of response from the dots. These observations are consistent with the effect of the signal frequency on the measured carrier concentration profile. To complete the picture and in order to distinguish the DLTS signature of the dots from that of the deep levels in GaInP, electron traps in the barrier material were also characterized. Two main electron traps, one with an activation energy of about 950 meV and the other having an activation energy of 450 meV, were present in all the samples.This publication has 23 references indexed in Scilit:
- Improved size homogeneity of InP-on-GaInP Stranski-Krastanow islands by growth on a thin GaP interface layerJournal of Crystal Growth, 1995
- Band filling at low optical power density in semiconductor dotsApplied Physics Letters, 1995
- Study of the two-dimensional–three-dimensional growth mode transition in metalorganic vapor phase epitaxy of GaInP/InP quantum-sized structuresApplied Physics Letters, 1994
- Spectroscopy of Quantum Levels in Charge-Tunable InGaAs Quantum DotsPhysical Review Letters, 1994
- Defects in epitaxial Si-doped GaInPJournal of Applied Physics, 1993
- Direct determination of the electron-tunneling escape time from a GaAs/As quantum well by transient-capacitance spectroscopyPhysical Review B, 1991
- Alloy Fluctuation in Mixed Compound Semiconductors as Studied by Deep Level Transient SpectroscopyJapanese Journal of Applied Physics, 1984
- Deep-level transient spectroscopy: A new method to characterize traps in semiconductorsJournal of Applied Physics, 1974
- Frequency dependence of C and ΔV/Δ(C−2) of Schottky barriers containing deep impuritiesSolid-State Electronics, 1973
- Admittance of p-n junctions containing trapsSolid-State Electronics, 1972