Preparation and characterization of I-III-VI_2 chalcopyrite semiconductor superlattice by Metalorganic Molecular Beam Epitaxy.

金属有机分子束外延制备I-III-VI_2黄铜矿半导体超晶格并表征。

• 批准号: 08650017
• 负责人: SHIRAKATA Sho
• 金额: $ 1.28万
• 依托单位: Ehime University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08650017/
• 关键词: I-III-V2 semicondactor; dulcopyrite semicondactor; snpalattice; Metalorganic Molecular Beam Epitary; Molecular Beam Epitary; I-III-Vl_2族半導体; カルコイパライト半導体; 質量スペクトル

Epitaxial layrs of CuGaSe_2 and CuAlSe_2 and the CuGaSe_2/CuAlSe_2 superlattice have been grown by the metalorganic molecular beam epitaxy (MOMBE) and the molecular beam epitaxy (MBE).1. MOMBE The c-axis-oriented epitaxial layrs of CuGaSe_2 and CuAlSe_2 have been grown on the GaAs (100) substrate. Based on the X-ray diffraction photoluminescence (PL), the modulation reflectance and Raman methods, the epilayrs are found to be of good quality. The CuAlSe_2/CuGaSe_2/GaAs heterostructure and the superlattice of the layr thickness of 200A have been prepared. However, the XPS in-depth profile did not reflect the periodicity of the superlattice. This suggests that the flatness of the layr is not so good and the improvement of the surface morphology is required.2. MBE Epilayrs of CuGaSe_2 and CuAlSe_2 have been grown on the GaAs (100) substrate with the RHEED in situ measurement. The epilayrs with flat surface have been realized by trimming the Cu/III ratio and by decreasing the growth rate. T … More he CuAlSe_2/CuGaSe_2/CuAlSe_2/GaAs single quantum wells and the (CuAlSe_2/CuGaSe_2)_m superlattices have been prepared. PL measurements indicated that the alloyed layr of Cu (Al, Ga) Se_2 has been formed at the CuAlSe_2/CuGaSe_2 interface due to the interdiffusion of Ga and Al. Therefore, superlattices with layr thickness less than 200A are mostly alloyed at the growth temperature of 600C.The low growth temperature of 550C has proven to be useful in order to reduce the interdiffusion to realize superlattice formation.3. Band calculation of superlattice Energy band structures of CuAlSe_2/CuGaSe_2 and CuAlSe_2/ZnSe superlattices have been calculated by the semi-empirical tight-binding method. Increase of the bandgap energy has been found for the CuAlSe_2/CuGaSe_2 superlattice with layr thickness of less than 200A.Increase of the bandgap energy up to 250 meV has been found CuAlSe_2/ZnSe superlattice in which the both CuAlSe_2 and ZnSe have bandgap energy of 2.67 eV.The new band engineering for obtaining the large bandgap semiconductor has been suggested using the CuAlSe_2/ZnSe superlattice. Less

采用金属有机分子束外延（MOMBE）和分子束外延（MBE）制备了CuGaSe_2和CuAlSe_2外延层和CuGaSe_2/CuAlSe_2超晶格。在GaAs（100）衬底上生长了CuGaSe_2和CuAlSe_2的c轴外延层。通过x射线衍射光致发光（PL）、调制反射率和拉曼光谱分析，发现薄膜质量良好。制备了CuAlSe_2/CuGaSe_2/GaAs异质结构和层厚为200A的超晶格。然而，XPS深度剖面并没有反映出超晶格的周期性。这说明层的平整度不是很好，需要对表面形貌进行改进。在GaAs（100）衬底上生长了CuGaSe_2和CuAlSe_2的MBE薄膜，并进行了原位测量。通过减小Cu/III比和降低生长速率，实现了表面平整的脱毛膜。此外，还制备了CuAlSe_2/CuGaSe_2/CuAlSe_2/GaAs单量子阱和（CuAlSe_2/CuGaSe_2）_m超晶格。PL测量结果表明，由于Ga和Al的相互扩散作用，在CuAlSe_2/CuGaSe_2界面处形成了Cu (Al, Ga) Se_2合金层，因此在生长温度为600℃时，层厚小于200A的超晶格大多合金化。550C的低生长温度有助于减少相互扩散，实现超晶格的形成。用半经验紧密结合的方法计算了CuAlSe_2/CuGaSe_2和CuAlSe_2/ZnSe超晶格的能带结构。发现层厚小于200A的CuAlSe_2/CuGaSe_2超晶格带隙能量增加。发现CuAlSe_2/ZnSe超晶格带隙能量增加到250 meV，其中CuAlSe_2和ZnSe的带隙能量均为2.67 eV。提出了利用CuAlSe_2/ZnSe超晶格获得大带隙半导体的新能带工程。少