Effect of different buffer-layers on near-infrared response of GaAs photocathodes

Yijun Zhang; Cheng Feng; Feng Shi; Xiaohui Wang; Xinxin Liu; Xiang Zhang; Yunsheng Qian

doi:10.1117/12.2261658

28 April 2017 Effect of different buffer-layers on near-infrared response of GaAs photocathodes

Yijun Zhang, Cheng Feng, Feng Shi, Xiaohui Wang, Xinxin Liu, Xiang Zhang, Yunsheng Qian

Proceedings Volume 10209, Image Sensing Technologies: Materials, Devices, Systems, and Applications IV; 1020918 (2017) https://doi.org/10.1117/12.2261658
Event: SPIE Commercial + Scientific Sensing and Imaging, 2017, Anaheim, CA, United States

Abstract

In view that enhancing near-infrared response of photocathodes is critical to the detection performance, we propose two technical approaches by changing the structure of buffer-layer underneath the active-layer, wherein one is to produce a graded band gap using the graded-composition structure, and the other is to produce a distributed Bragg reflector using the AlAs/GaAs supperlattice structure. Three types of reflection-mode GaAs photocathode samples grown by molecular beam epitaxy were prepared under the same condition. By comparison of activation photocurrent and spectral response among the three different samples, it is found that compared with the conventional sample, the samples with graded-composition and distributed Bragg reflector can obtain higher photocurrent and better response. The measured results of spectral response indicate that the samples without a distributed Bragg reflector exhibit a typical smooth spectral behavior, while the spectral response of the sample with a distributed Bragg reflector structure has a different resonance feature. The sample with the distributed Bragg reflector structure can obtain higher response than those without distributed Bragg reflector at some near-infrared wavelength positions. The peak positions of spectral response curve agree quite well with the dip positions in the reflectivity spectrum. This agreement demonstrates that the response enhancements are ascribed to the resonant absorption effect.

Citation Download Citation

Yijun Zhang, Cheng Feng, Feng Shi, Xiaohui Wang, Xinxin Liu, Xiang Zhang, and Yunsheng Qian "Effect of different buffer-layers on near-infrared response of GaAs photocathodes", Proc. SPIE 10209, Image Sensing Technologies: Materials, Devices, Systems, and Applications IV, 1020918 (28 April 2017); https://doi.org/10.1117/12.2261658

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
6 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Gallium arsenide

Reflectivity

Absorption

Near infrared

Distributed Bragg reflectors

Cesium

Quantum efficiency

Show All Keywords

Keywords/Phrases

Search In:

Publication Years