Substrate-Free Chemical Vapor Deposition of Large-Scale III-V Nanowires for High-Performance Transistors and Broad-Spectrum Photodetectors

Large-scale growth of high-quality III-V nanowires (NWs) on an expected substrate is challenging the next-generation optoelectronic devices. In this work, high-quality III-V NWs of binary GaSb, GaAs and ternary GaAsxSb1-x, InxGa1-xAs are successfully prepared on the hard substrates of SiO2/Si, amorphous glass and flexible substrates of mica, glass fiber, and carbon cloth by adopting the simple and low-cost metal-catalyzed chemical vapor deposition (CVD) method. The homogeneity of morphology, crystallinity, and stoichiometry is checked by scanning electron microscopy, X-ray diffraction, high-resolution transmission electron microscopy, and energy dispersive X-ray spectroscopy, implying the high-quality phase purity of III-V NWs on various substrates. When configured into NW field-effect-transistors, the electrical properties, such as field-effect mobilities of GaSb NWs grown on various substrates show relatively similar satisfactory values. Meanwhile, the as-fabricated GaSb NWs photodetector exhibits excellent broad-spectrum photodetection ability from visible to near-infrared bands. Furthermore, by adopting a home-made stepper CVD method, large-scale GaSb NWs with uniform morphology, crystallinity, stoichiometry, and electrical properties are prepared on glass. All results guide the easy growth of high-quality functional NWs on any expected substrates for further photoelectronic applications.