机构地区: 厦门大学物理与机电工程学院物理学系
出 处: 《发光学报》 2004年第2期168-172,共5页
摘 要:
利用变温光致发光(PL)谱及时间衰退发光谱研究了一系列CaP_(1-x)N_x混晶的光学性质。GaP_(1_x)N_x混晶的PL谱从低组分的NN对束缚激子及其声子伴线到高组分杂质带发光的特征,表现出明显的带降降低的趋势。测量结果显示,在组分x≥0.24%的样品的发光谱中NN_1能量之下已经开始出现几个新的束缚态,对其激活能的拟合及对时间衰退发光谱的分析表明,新的束缚态一方面仍保留有N束缚激子的性质,另一方面又表现出有别于NN对束缚激子的发光机制。说明新的束缚态有可能由新的N原子组成(如NNN原子)或与NN对束缚激子存在着某种相互作用。
GaP_(1-x)N_x alloy is a remarkable and promising semiconductor for its giant band-gap bowing effect
and its potential application in optoelectronic devices. In this article, we carried out a series of studies on the
optical properties of GaP_(1-x)N_x alloys, especially focusing on the samples with composition x=0.24%, 0.6%,
0.81%, using temperature-dependent photoluminescence(PL) speetra and transient photoluminescense spectra. At
17 K PL spectra, the GaP_(1-x)N_x alloys exhibit an obvious tendency of band-gap reduction with increasing composi-
tion x. When composition x<0.24%, the NN_1 zero-phonon line and its replicas in GaP_(1-x)N_x alloys are well re-
solved, displaying similar characteristic to dilute nitrogen doped GaP; while 0.24%