Characterization and physics of top-down silicon nanowire phototransistors

Arthur Zhang; James Cheng; Hongkwon Kim; Yisi Liu; Yu-Hwa Lo

doi:10.1117/12.841201

22 January 2010 Characterization and physics of top-down silicon nanowire phototransistors

Arthur Zhang, James Cheng, Hongkwon Kim, Yisi Liu, Yu-Hwa Lo

Proceedings Volume 7608, Quantum Sensing and Nanophotonic Devices VII; 76081D (2010) https://doi.org/10.1117/12.841201
Event: SPIE OPTO, 2010, San Francisco, California, United States

Abstract

Nanowire photodetectors of a variety of materials have been attracting increased attention due to their potential for very high sensitivity detection. Silicon photodetectors are of particular interest for detection in the visible spectrum, having many benefits including cost of substrate, ease of processing, and ability for integration with conventional fabrication techniques. Using top-down fabrication techniques results in additional benefits of precise control of number, geometry, and placement of these wires. To demonstrate the potential of these devices, top-down, vertical silicon nanowire phototransistor arrays have been fabricated using ebeam lithography and deep reactive ion and inductively coupled plasma etching. These devices show a much higher phototransistive gain over nanowire photodiodes with similar geometry under illumination from a 635nm laser. Low temperature measurements also show the dependence of dark current and sensitivity on temperature. The mechanism responsible for this gain is shown to be dominated by the large surface-to-volume ratio of nanowires where charge capture and recombination at the surface creates a radial gate bias which is modulated with light intensity. 3D numerical simulations validate this mechanism and further show the dependence of device behavior on nanowire doping, geometry, and surface state density. This will allow for the precise engineering of these devices to achieve the maximum sensitivity obtainable as we strive for the ultimate goal of single photon resolution.

Citation Download Citation

Arthur Zhang, James Cheng, Hongkwon Kim, Yisi Liu, and Yu-Hwa Lo "Characterization and physics of top-down silicon nanowire phototransistors", Proc. SPIE 7608, Quantum Sensing and Nanophotonic Devices VII, 76081D (22 January 2010); https://doi.org/10.1117/12.841201

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