Presentation Information
[16a-WL2_101-7]Tuning Schottky Barrier Characteristics at NiAl/p-Si Interfaces for Scalable Infrared Photodetectors
〇(D)ChihHsing WANG1,2, Andrea Ruiz-Perona1,2, Hiroyuki Yamada1, Thien Duc Ngo1, Toan Phuoc Tran1,2, Keisuke Watanabe1, Tadaaki Nagao1,2 (1.NIMS, 2.Hokkaido Univ.)
Keywords:
NiAl/p-Si Interface,Schottky Barrier Height,Infrared Photodetector
Photoresponsive materials are fundamental to the advancement of energy harvesting and remote sensing, where infrared (IR) radiation is the primary signal source. However, conventional infrared photodetectors such as bolometers often struggle with spectral selectivity and scalability. Nickel–aluminum (NiAl) alloys have recently gained growing attention as potential materials for next-generation electronic and plasmonic devices due to their superior thermal stability and good electro-optical properties. Research indicates that NiAl ultrathin films can achieve high electrical conductivity compatible with standard copper contacts, offering a pathway for highly integrated nanoscale devices. Furthermore, theoretical models suggest that NiAl/Si interfaces can form Schottky barriers within the 0.4–0.7eV range, which is ideal for eliminating the limitations of semiconductor bandgaps via interface engineering. In this study, we focus on modulating the Schottky barrier height (SBH) at NiAl/p-Si interfaces by optimizing thin-film fabrication strategies.Building upon the process proposed by Tran, three deposition conditions were compared: room-temperature (RT) deposition, RT deposition with post-deposition annealing (PDA), and a two-step “Combined-NiAl” method. The two-step process combines in situ high-temperature growth followed by an additional deposition of post-annealed film to balance the internal crystallinity and surface flatness to enhance the surface polarizability and optical loss. I–V measurements show a strong dependence of Schottky barrier height (SBH) on thermal budget, with the Combined-NiAl sample achieving the highest SBH (~0.6 eV). Future work will focus on analyzing interfacial composition and crystallographic characteristics to further improve film crystallinity and optoelectronic response.