Time-resolved photoluminescence investigations on HfO2-capped InP nanowires

Summary, in English

We have employed time-resolved photoluminescence (PL) spectroscopy to study the impact of HfO2 surface capping by atomic layer deposition (ALD) on the optical properties of InP nanowires (NWs). The deposition of high-kappa dielectrics acting as a gate oxide is of particular interest in view of possible applications of semiconductor NWs in future wrap-gated field effect transistors (FETs). A high number of charged states at the NW-dielectrics interface can strongly degrade the performance of the FET which explains the strong interest in high quality deposition of high-kappa dielectrics. In the present work we show that time-resolved spectroscopy is a valuable and direct tool to monitor the surface quality of HfO2-capped InP NWs. In particular, we have studied the impact of ALD process parameters as well as surface treatment prior to the oxide capping on the NW-dielectrics interface quality. The best results in terms of the surface recombination velocity (S-0 = 9.5 x 10(3) cm s(-1)) were obtained for InP/GaP core/shell NWs in combination with a low temperature (100 degrees C) ALD process. While the present report focuses on the InP material system, our method of addressing the surface treatment for semiconductors with high-kappa dielectrics will also be applicable to nanoelectronic devices based on other III/V material systems such as InAs.

• Author: S. Muench; S. Reitzenstein; Magnus Borgström; Claes Thelander; Lars Samuelson; L. Worschech; A. Forchel
• Department/s: Solid State Physics; NanoLund: Centre for Nanoscience
• Publishing year: 2010
• Language: English
• Publication/Series: Nanotechnology
• Volume: 21
• Issue: 10
• Links: http://dx.doi.org/10.1088/0957-4484/21/10/105711
• Document type: Journal article
• Publisher: IOP Publishing
• Topic: Nano Technology
• Status: Published
• ISBN/ISSN/Other: ISSN: 0957-4484