This theses investigates the carrier dynamics in Indium Nitride thin films grown on Si(111) substrates by means of ultrafast time-resolved photoluminescence (TRPL) apparatus. The study of energy relaxation shows hot phonon effective is prominent at photogenerated carrier concentration above 4¡Ñ10^18cm^-3 and become insignificant at carrier concentration below 7¡Ñ10^17cm^-3. Effective phonon emission times in the range of 116 to 23 femtoseoncds are obtained from the time evolution of carrier temperature assuming that the carrier-LO-phonon interaction is the dominant energy relaxation process. In the study of carrier recombination, the TRPL¡¦s are studied at the peak energies of the time-integrated PL at various lattice temperatures and are converted to decay rates with a rate equation, which includes the nonradiative and radiative coefficients, and a nonlinear dependence of PL intensity on the photogenerated carrier concentration. The increase with temperatures of the Shockley-Read-Hall rates implies that, in addition to the mid-gap defect states, a thermally activated trapping may become prominent at high lattice temperatures due to the increased kinetic energy gained by the carriers. The radiative recombination is the dominated recombination mechanism at low temperature but become trivial at high temperature. The fitted radiative coefficient at a temperature of 35K is consistent to the theoretical prediction. The Auger recombination exhibits a quadratic dependence on carrier concentration and becomes effective at high carrier concentration and at high temperature. The fitted Auger recombination coefficients are comparable to those of InGaAs and InGaAsP materials with band gap energies in the range of 0.6-0.8eV.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0214108-121135 |
| Date | 14 February 2008 |
| Creators | Lin, Guan-Ting |
| Contributors | Yung-Sung Chen, Meng-En Lee, Li-Wei Tu, Der-Jun Jang, I-Min Jiang |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214108-121135 |
| Rights | withheld, Copyright information available at source archive |
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