氧化铝薄膜对硫钝化InP材料光学稳定性的影响

The Influence of Al_2O_3 Films on the Optical Stability of S-passivated InP

利用原子层沉积法(ALD)在硫钝化后的n型InP表面沉积Al2O3薄膜进行二次钝化处理。通过光致发光(PL)测试和原子力显微镜(AFM)测试对样品的光学性质及表面形貌进行表征。硫钝化能够有效降低样品的表面态密度及无辐射复合几率,因此样品PL发光强度得到了极大提高。而样品表面的Al2O3可防止钝化层被氧化,尽管相对于沉积Al2O3薄膜前样品的光致发光强度有所降低,但样品的稳定性得到了改善,因此可进一步提高样品的发光性能。

Al2O3 films were deposited on the surface of sulfur （S）-passivated n-type InP using atomic deposi- tion （ALD）. The optical properties and surface morphology of the treatments on InP were investigated by photolumi- nescence （PL） measurement and atomic force microscopy （AFM） measurement. The surface states density and nonra- diative recombination velocity were reduced effectively with the S-treatment and thus the PL intensity was enhanced greatly. While the Al2O3 films could prevent the passivation layer from being oxidized, although the PL intensity de- creased compared with the uncoated samples, but the stability of the coated samples was improved, and therefore the luminescent properties of the samples can be further enhanced.