掺锰磷化铟中1.18eV辐射的施主受主对辐射性质的研究

通过对掺锰磷化铟的1.18eV辐射的频率响应谱(FRS)及辐射峰随激发强度的位移的研究得到了明确的证据,确认这个光致发光辐射的施主受主对(DAP)复合的性质。一个和Mn2+相关的复合跃迁过程被提出用以解释有关的实验结果。

INVESTIGATION OF DAP TRANSITION NATURE OF 1.18eV EMISSION BAND IN InP:Mn

Typical DAP (donor acceptor pair) recombination behaviours were found for the 1.18eV emission in InP and reported in this paper. The evidences for that the 1.18eV emission band in InP is associated with Mn impurity centers in InP has been published before. No evidence for the DAP nature of this band has been reported previously although DAP recombination as one of possible transition mechanisms was suggested before. The shape line structure of DAP emission has not been reported to be clearly identified in Ⅲ-Ⅴ semiconductor compounds with direct energy gap. In this kind of materials the DAP nature can be established by observing the time-resolved spectra and the intensity-dependent peak shift of the luminescence. The methode of frequency response spectroscopy (FRS) and luminescence decay measurement using boxcar were used in the present work and the emission peaks of this band corresponding long live emission shifting to low energy side as an evidence for the DAP nature was obtained in all the samples measured. The excitation intensity dependent peak shift about 1.8meV was also observed in these samples. The results provides convincing evidence that 1.18eV emission in InP is from DAP recombination. The neutral state of Mn ions in Ⅲ-Ⅴ compounds is Mn3+ with configuration d4 but the half filled shall configuration d5 is strongly favoured on the ground of energy stability. The ODMR and EPR investigation, which was published previously, also suggested that the transition of 1.18eV band be related to Mn2+ ion. This implies that the DAP transition of 1.18eV can be expressed as Mn2+]h + D°→Mn2+]+D+ + hv1·18eV. where D represents inadvertent donors in InP and Mn2+]h means that a hole is loosely bound to half shall state Mn2+. Mn2+] h keeps electrically neutral.