The study of interface quality in HfO 2 /Si films probed by second harmonic generation

• Published in: Journal of physics. D, Applied physics Vol. 57; no. 41; p. 415105
• Main Authors: Ye, Li, Zhang, Libo, Wang, Shaotong, Zhao, Weiwei, Huang, Chongji, Gao, Wenshuai, Liu, Xue, Li, Tiaoyang, Li, Tao, Min, Tai, Tian, Mingliang, Chen, Xuegang
• Format: Journal Article
• Language: English
• Published: 18.10.2024
• ISSN: 0022-3727; 1361-6463
• DOI: 10.1088/1361-6463/ad61f9

Abstract Time-dependent second harmonic generation (TD-SHG) is an emergent sensitive and non-contact method to qualitatively/quantitively characterize the semiconductor materials, which is closely related to the interfacial electric field. Here, the TD-SHG technique is used to study the interface quality of atomic layer deposited 15 nm HfO 2 /Si ( n -type/ p -type) samples, which is compared to the conventional electrical characterization method. A relation between the interface state density and the time constant extracted from TD-SHG is revealed, indicating that TD-SHG is an effective method to evaluate the interface state density. In addition, the dopant type and dopant density can be disclosed by resolving the dynamic process of TD-SHG. The scenario of interfacial electric field between the initial electric field and the laser-induced electric field is proposed to explain the time-dependent evolution of SHG signal. In conclusion, the TD-SHG is a sensitive and non-contact method as well as simple and fast to characterize the semiconductor materials, which may facilitate the semiconductor in-line testing.