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Abstract 2D van der Waals (vdW) magnets open landmark horizons in the development of innovative spintronic device architectures. However, their fabrication with large scale poses challenges due to high synthesis temperatures (>500 °C) and difficulties in integrating them with standard complementary metal‐oxide semiconductor (CMOS) technology on amorphous substrates such as silicon oxide (SiO2) and silicon nitride (SiNx). Here, a seeded growth technique for crystallizing CrTe2films on amorphous SiNx/Si and SiO2/Si substrates with a low thermal budget is presented. This fabrication process optimizes large‐scale, granular atomic layers on amorphous substrates, yielding a substantial coercivity of 11.5 kilo‐oersted, attributed to weak intergranular exchange coupling. Field‐driven Néel‐type stripe domain dynamics explain the amplified coercivity. Moreover, the granular CrTe2devices on Si wafers display significantly enhanced magnetoresistance, more than doubling that of single‐crystalline counterparts. Current‐assisted magnetization switching, enabled by a substantial spin–orbit torque with a large spin Hall angle (85) and spin Hall conductivity (1.02 × 107ℏ/2e Ω⁻¹ m⁻¹), is also demonstrated. These observations underscore the proficiency in manipulating crystallinity within integrated 2D magnetic films on Si wafers, paving the way for large‐scale batch manufacturing of practical magnetoelectronic and spintronic devices, heralding a new era of technological innovation.
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DNA-based doping and fabrication of PN diodes
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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- PAR ID:
- 10493265
- Publisher / Repository:
- Frontiers in Nanotechnology
- Date Published:
- Journal Name:
- Frontiers in Nanotechnology
- Volume:
- 6
- ISSN:
- 2673-3013
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/fnano.2024.1291328
