An on-chip approach for fabricating ferromagnetic/semiconductor-nanotip heterojunctions is demonstrated. The high-density array of Si nanotips (SiNTs) is employed as a template for depositing La0.7Sr 0.3MnO3 (LSMO) rods with a pulsed-laser deposition method. Compared with the planar LSMO/Si thin film, the heterojunction shows a large enhancement of room temperature magnetoresistance (MR) ratio up to 20% under 0.5 T and a bias current of 20 μA. The MR ratio is found to be tunable, which increases with increasing external bias and the aspect ratios of the nanotips. Electric-field-induced metallization, in conjunction with nanotip geometry, is proposed to be the origin for the giant MR ratio.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering