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This paper reports the fabrication of silicon PN diode by using DNA nanostructure as the etching template for SiO2and also as then-dopant of Si. DNA nanotubes were deposited ontop-type silicon wafer that has a thermal SiO2layer. The DNA nanotubes catalyze the etching of SiO2by HF vapor to expose the underlying Si. The phosphate groups in the DNA nanotube were used as the doping source to locallyn-dope the Si wafer to form vertical P-N junctions. Prototype PN diodes were fabricated and exhibited expected blockage behavior with a knee voltage ofca.0.7 V. Our work highlights the potential of DNA nanotechnology in future fabrication of nanoelectronics.
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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
- PAR ID:
- 10449613
- 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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