DNA Immobilization on GaP(100) Investigated by Kelvin Probe Force Microscopy

David Richards, Purdue University
Dmitry Zemlyanov, Purdue University
Rafay Asrar, Purdue University - Main Campus
Yena Chokshi, Purdue University - Main Campus
Emily M. Cook, Purdue University - Main Campus
Thomas Hinton, Purdue University - Main Campus
Xinran Lu, Purdue University - Main Campus
Viet Nguyen, Purdue University - Main Campus
Neil Patel, Purdue University - Main Campus
Jonathan Usher, Purdue University - Main Campus
Sriram Vaidyanathan, Purdue University - Main Campus
David Yeung, Purdue University - Main Campus
Albena Ivanisevic, Birck Nanotechnology Center, Purdue University

Date of this Version

9-2010

This document has been peer-reviewed.

 

Abstract

Understanding changes in the properties of semiconductor materials after immobilization of biomolecules on the surface is essential for the fabrication of well-tuned and programmable devices. The work examines changes in the properties of gallium phosphide (GaP) after modification with an organic linker, a single stranded DNA, and its complementary strand. We investigated changes in surface potential with Kelvin probe force microscopy (KPFM). Analysis revealed that a more ordered adlayer of ssDNA was present when a lower concentration of linker molecule was used. KPFM data combined with coverage data obtained from X-ray photoelectron spectroscopy (XPS) further confirmed this result. Successful hybridization with the complementary strand was confirmed by both KPFM and Raman spectroscopy. The results indicate that one can control the amount of DNA on the surface by changing the initial concentration of the organic linker, and thus modulate the surface potential of the semiconductor material.

Discipline(s)

Engineering | Nanoscience and Nanotechnology

 

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