Up-Conversion 螢光量測系統的架設和極小尺寸氮化銦奈米棒陣列的變溫螢光量測

Abstract

Photoluminescence (PL) can characterize the emission property of various semiconductors, which is in turn used to understand the purity, crystalline quality, disorders, etc. of semiconductors such as InGaAs and InP. In this work, we have intensively studied the PL from vertically aligned indium nitride (InN) nanorods (NRs) grown on Si (111) substrates. In particular, the abnormal behavior of PL from InN NRs with the rod diameter comparable to the surface electron accumulation layer was observed. Exceptionally large activation energy of the NRs with the critical diameter implies that holes within these narrow NRs need to surpass the band bending near the surface in order to recombine with electrons accumulated in the surface layer. Time-resolved PL (TRPL) also plays an important role in providing the information of dynamic behavior of radiative recombination of semiconductors. However, time-correlated single photon counting method, which is typically used for life science, has rather long time resolution for elucidating the dynamic phenomena of semiconductors. In the second part of this thesis, the development of up-conversion PL system is introduced. The basic concept of sum frequency generation and its application to the ultrafast luminescence spectroscopy are described in detail. Furthermore, the optical configuration, photon counting technique, and the automatic control of the up-conversion PL system are demonstrated. The theoretical calculation of TRPL signal level are compared to the preliminary experimental results of our system.

Photoluminescence (PL) can characterize the emission property of various semiconductors, which is in turn used to understand the purity, crystalline quality, disorders, etc. of semiconductors such as InGaAs and InP. In this work, we have intensively studied the PL from vertically aligned indium nitride (InN) nanorods (NRs) grown on Si (111) substrates. In particular, the abnormal behavior of PL from InN NRs with the rod diameter comparable to the surface electron accumulation layer was observed. Exceptionally large activation energy of the NRs with the critical diameter implies that holes within these narrow NRs need to surpass the band bending near the surface in order to recombine with electrons accumulated in the surface layer. Time-resolved PL (TRPL) also plays an important role in providing the information of dynamic behavior of radiative recombination of semiconductors. However, time-correlated single photon counting method, which is typically used for life science, has rather long time resolution for elucidating the dynamic phenomena of semiconductors. In the second part of this thesis, the development of up-conversion PL system is introduced. The basic concept of sum frequency generation and its application to the ultrafast luminescence spectroscopy are described in detail. Furthermore, the optical configuration, photon counting technique, and the automatic control of the up-conversion PL system are demonstrated. The theoretical calculation of TRPL signal level are compared to the preliminary experimental results of our system.