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Title: DNA‐Based Strategies for Site‐Specific Doping
Abstract

The development of novel doping strategies compatible with high‐resolution patterning and low cost, large‐scale manufacturing is critical to the future development of electronic devices. Here, an approach to achieve nanoscale site‐specific doping of Si wafer using DNA as both the template and the dopant carrier is reported. Upon thermal treatment, the phosphorous atoms in the DNA diffuse into Si wafer, resulting in doping within the region right around the DNA template. A doping length of 30 nm is achieved for 10 s of thermal treatment at 1000 °C. Prototype field effect transistors are fabricated using the DNA‐doped Si substrate; the device characteristics confirmed that the Si is n‐doped. It is also shown that this approach can be extended to achieve both n‐type and p‐type site‐specific doping of Si by using DNA nanostructures to pattern self‐assembled monolayers. This work shows that the DNA template is a dual‐use template that can both pattern Si and deliver dopants.

 
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Award ID(s):
1901864
NSF-PAR ID:
10449613
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Functional Materials
Volume:
31
Issue:
1
ISSN:
1616-301X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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