离子注入诱导的具有两个不同发射波长的混合双量子阱结构

叙述了磷离子注入方法诱导具有不同发射波长的InGaAsP双量子阱结构的混合,并通过光致发光谱和断面透射电子显微术对量子阱混合的程度进行了研究。在特定条件下快速热退火处理后,光致发光谱显示,在离子注入剂量低于7×10¹¹/cm²情况下,两个阱的谱峰能保持较好的分离,注入剂量从10¹¹ /cm²增大到10¹²/cm²的过程中,两个阱的带隙蓝移值都似乎存在一个极大值,并且在同样的条件下,上阱(发射波长为1.52 μm)的带隙蓝移值较下阱(发射波长为1.59 μm)大些。当离子注入剂量达到10¹²/cm²时,上阱的谱峰近乎消失,双阱光致发光谱出现了一个谱峰。用断面透射电子显微术对原生长样品与带隙蓝移具有极大值的退火样品进行微结构比较,结果显示,对比原生长样品,退火样品的晶格原子基本得到修复,但阱与垒间的界面显得模糊,这说明离子注入导致两阱完全混合。

Ion-implantation-induced Intermixing of Double Quantum Wells with Different Emission Wavelengths

In this work, phosphorus ion-implantation-induced intermixing of InGaAsP double quantum wells (DQWs) with different emission wavelengths was investigated by photoluminescence (PL) spectrum and cross-sectional transmission electron microscopy (TEM). After thermal annealing under specific conditions, the PL showed that the PL peaks of both wells always remain well separate under the condition of a low implanting dose (less than 7×1011/cm2), the bandgap blue-shift for each well appears a maximum as the implantation doses are increased from 1011to 1012/cm2, and the blue-shift from the upper quantum well (QW) is larger than that from the lower QW under the same conditions of implantation and annealing. When the ion dose is 1012/cm2, the PL peak of the upper QW is nearly negligible and the peaks from DQWs appear to combine together as one peak. Comparing as-grown sample with annealed sample appearing maximum blue-shift by cross-sectional TEM, the boundaries of annealed sample between wells and barriers become vague, indicating that the ion implantation results in a total intermixing of two wells.