Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants |
Applied materials science/Crystal engineering
|Research Institution||Osaka University (2003)|
Nagoya University (2001-2002)
FUJIWARA Yasufumi Osaka University, Graduate School of Engineering, Professor, 大学院・工学研究科, 教授 (10181421)
TAKAHEI Ken-ichiro Anritsu Co., Central Research Center, Head Researcher, 研究所, 主席研究員
TAKEDA Yoshikazu Nagoya University, Graduate School of Engineering, Professor, 大学院・工学研究科, 教授 (20111932)
YOSHIDA Hiroshi Osaka University, he Institute of Scientific and Industrial Research, Professor, 産業科学研究所, 教授 (30133929)
野々垣 陽一 岡崎国立共同研究機構, 分子科学研究所, 助手 (40300719)
田渕 雅夫 名古屋大学, 工学研究科, 講師 (90222124)
町田 英明 (株)トリケミカル研究所, 技術開発本部, 主席研究員
|Project Period (FY)
2001 – 2003
Completed (Fiscal Year 2003)
|Budget Amount *help
¥12,600,000 (Direct Cost: ¥12,600,000)
Fiscal Year 2003: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 2002: ¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 2001: ¥7,700,000 (Direct Cost: ¥7,700,000)
|Keywords||rare-earth-doped III-V / semiconductors / materials for new semiconductor lasers / atomically-controlled growth / stimulated emission / erbium / doubleheterostructures / control of heterointerface|
Rare-earth (RE) doped semiconductors have gained significant attention as a promising new class of materials that emit light from the RE 4f shell by means of electrical injection, in which the energy of electron-hole pairs is transferred to the RE shell. The intra-4f shell transitions of RE ions give rise to sharp emission lines whose wavelengths are largely independent of both the host materials and temperature. This stability occurs because the filled outer 5s and 5p electron shells. screen transitions within the inner 4f electron shell from the interaction with the host. The intra-4f shell transitions from the first excited state (4^I_<13/2>) to the ground state (4^I_<15/2>) of Er^<3+> ions at around 1.5 μm is of special interest because the wavelength matches the minimum loss region of silica fibers used in optical communications.
In this research project, we investigated atomically-controlled growth of Er-doped GaAs with high quality for new-type light-emitting devices. Results obt
ained experimentally are summarized as follows
1)By optimizing reactor structure and growth temperature, the abrupt change in composition at the heterointerface consisting of different group-V elements was successfully obtained.
2)Er-20 configuration was selectively formed by codoping Er and O to GaAs, resulting in the increase in PL intensity by two orders in magnitude: The amount of O in growth ambient played an important role for the intensity increase.
3)Er-related luminescence was observed in GaInP/GaAs : Er, O/GaAs doubleheterostructures by injecting, current at room temperature. The EL spectrum was dominated by Er-20 lines, suggesting a successful formation of the Er-20 center and a preferential excitation of the center by current injection.
4)The current density dependence of the EL intensity revealed an extremely large excitation cross section of Er ions by current injection, approximately 10^<-15> cm^2. The large excitation cross section was confirmed by time-resolved measurements. of the EL intensity. It is by two orders in magnitude larger than that of Er-doped Si LEDs (6x10^<-17> cm^2). Less