Effects of Different Oxidation Degrees of Graphene Oxide on P-Type and N-Type Si Heterojunction Photodetectors.

Ching-Kuei Shih,Chun-Wei Chiu,Yen-Chun Chen,Yu-Tang Ciou,Chu-Hsuan Lin,Yu-Ru Li,Jia-Syun Jheng

doi:10.3390/nano8070491

Ching-Kuei Shih, Chun-Wei Chiu + Show 5 more

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https://doi.org/10.3390/nano8070491

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Abstract

Oxygen-containing functional groups in graphene oxide (GO), a derivative of graphene, can widen the bandgap of graphene. In this study, we varied the amount of hydrogen peroxide used to prepare GO samples with different degrees of oxidation. Transmittance measurement, Raman spectroscopy, and X-ray photoelectron spectroscopy were used to completely characterize the change in oxidation degree. The effects of oxidation degree on p-type and n-type Si heterojunction photodetectors were compared. Notably, GO with a lower oxidation degree led to a larger photoresponse of p-type Si, whereas that with a higher oxidation degree achieved a larger photoresponse of n-type Si.

Highlights

IntroductionHeterojunction photodetectors combine two types of materials for light detection, and Si is the optimal choice for one of the two materials due to mature and cheap Si complementary metal–oxide–
Heterojunction photodetectors combine two types of materials for light detection, and Si is the optimal choice for one of the two materials due to mature and cheap Si complementary metal–oxide–semiconductor (CMOS) technology with Si acting as the substrate [1,2,3]
We propose that high-oxidation-degree graphene oxide (GO) is suitable for GO/n-Si heterojunction details of the experimental procedures are as photodetectors and low-oxidation-degree is suitable for GO/p-type Si substrates (p-Si) heterojunction photodetectors

Summary

Introduction

Heterojunction photodetectors combine two types of materials for light detection, and Si is the optimal choice for one of the two materials due to mature and cheap Si complementary metal–oxide–. The common graphene-based materials in Si heterojunction photodetectors are composed of graphene/Si [5,6,7] or reduced-graphene-oxide (rGO)/Si [8,9,10] structures. In these studies, graphene or rGO is typically only used as the electrode in Schottky diodes. Since GO has the advantage of an opened bandgap over graphene, the influence of oxidation degrees is a meaningful subject. We propose that highoxidation-degree GO is suitable for GO/n-Si heterojunction photodetectors and low-oxidation-degree.

Experiments

Characterization

Transmittance

Electrical

Conclusions