Transformation from Film to Nanorod via a Sacrifical Layer: Pulsed Laser Deposition of ZnO for Enhancing Photodetector Performance

Sin-Liang Ou,Fei-Peng Yu,Dong-Sing Wuu

doi:10.1038/s41598-017-14592-6

Sin-Liang Ou, Fei-Peng Yu + Show 1 more

Open Access

https://doi.org/10.1038/s41598-017-14592-6

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Abstract

A novel fabrication method for single crystalline ZnO nanorods by pulsed laser deposition (PLD) using a chemical-bath-deposited ZnS seed layer is proposed. For the substrate temperature (Ts) lower than 700 °C, the PLD-ZnO showed a polycrystalline phase and film-type morphology, resulting from the ZnS seed layer with a cubic phase. However, the ZnS film became a sacrifical layer and single crystalline ZnO(002) nanorods can be achieved at Ts of 900 °C, where ZnS was decomposed to zinc metals and sulfur fumes. The transformation from ZnO film to nanorod microstructure was demonstrated with the change of ZnS layer into Zn grains. Enhanced performance of the metal-semiconductor-metal photodetectors were fabricated with ZnO/ZnS samples grown at Ts of 500, 700, and 900 °C. The responsivities (@1 V and 370 nm) of these three devices were 1.71, 6.35, and 98.67 A/W, while their UV-to-visible discrimination ratios were 7.2, 16.5, and 439.1, respectively. Obviously, a higher light-capturing efficiency was obtained in the 900 °C-grown ZnO/ZnS device owing to its one-dimensional nanostructure with high crystal quality. The results indicate PLD combined with a sacrifical nanostructure is a promising method for obtaining high-quality ZnO nanorods, which paves the way for the fabrication of high performance ZnO-based devices.

Highlights

A novel fabrication method for single crystalline ZnO nanorods by pulsed laser deposition (PLD) using a chemical-bath-deposited ZnS seed layer is proposed
We can observe that the 900 °C-grown PLD-ZnO prepared on the CBD-ZnS seed layer was composed of the ZnO nanorods with the diameter approximately 100– 200 nm
We have presented a novel technique for the growth of single crystalline ZnO nanorods by conventional PLD combined with a sacrifical nanostructure

Summary

Introduction

A novel fabrication method for single crystalline ZnO nanorods by pulsed laser deposition (PLD) using a chemical-bath-deposited ZnS seed layer is proposed. ZnO-based nanostructures are prepared via aqueous solution technique, vapor–liquid–solid process, and hydrothermal method These ZnO nanostructures grown by the as-mentioned methods are almost polycrystalline with low crystal qualities. Most of the ZnO-based nanostructure-type devices are fabricated by aqueous solution technique, vapor–liquid–solid process, and hydrothermal method. Some drawbacks such as the large leakage current usually occurred in the devices prepared by these methods. By choosing suitable seed layers, the novel method will be used for the device fabrications with other oxide materials (such as Ga2O3, In2O3, TiO2, and so on), expanding the practicality of this growth technique

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