Metamorphic multiple quantum dots (QDs) on GaAs substrates were grown by molecular beam epitaxy (MBE). The metamorphic layers including In0.15Ga0.85As and AlAs were in-situ annealed at high temperature (T=800oC) to reduce the dislocations. InGaAs QDs were then grown on the metamorphic layers.
We use the laser source and pulse voltage to modulate the dielectric constant of the samples in modulation reflectance measurement system. The inner electric field is obtained from the photo-reflectance Franz-Keldysh oscillation (FKO), and the energy transition is analyzed though the photoluminescence (PL), electroluminescence (EL), and photocurrent (PC) spectroscopy.
The electroluminescence wavelength of InAs QDs on metamorphic In0.15Ga0.85As substrate can be push to ~1460 nm. The optimum emission quality is obtained by inserting 3-nm GaAs layer beneath the In0.15Ga0.85As buffer layer. The In0.15Ga0.85As buffer is flatter because of the GaAs layer, and the QDs become more uniform. We expect the InAs QDs on metamorphic GaAs substrate can be applied for optical communication in the £f=1550 nm region.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0709109-123806 |
| Date | 09 July 2009 |
| Creators | Chen, Shiang-Lin |
| Contributors | Yi-Jen Chiu, Tien-Tsorng Shih, Wood-Hi Cheng, Mau-Phon Houng, Tsong-Sheng Lay |
| 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-0709109-123806 |
| Rights | not_available, Copyright information available at source archive |
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