Influence of Hydrogen Flow Rates Annealing on the Structural, Optical, and Electrical Properties of Sol-Gel Synthesized Fe doped In2O3 Films

Abstract

Diluted magnetic semiconductors (DMSs) have always been of great interest to study due to their wide applications in spintronics. This research was carried out to study the influence of different hydrogen gas flow rates annealing on the physical properties of Fe doped indium oxide. In 1.92 Fe 0.08 O 3 thin films were prepared by a sol-gel method and followed by a spin coating technique. Different flow rates of hydrogen gas were applied during the annealing process. All samples showed high orientation along the (222) direction and exhibit a polycrystalline structure. Grain size increased as the flow rate increased due to the stronger reduction of H 2 . FTIR studies showed the existence of an O-H bond in the range of 3000 -4000 cm -1 and it was caused by the flow of H 2 gas during the annealing process. The resistivity of In 1.92 Fe 0.08 O 3 thin films decreased and the carrier concentration increased with increasing hydrogen flow rates. This work has significance on the size-dependent properties and the chemical bonding in Fe doped In 2 O 3 films. Keywords: FTIR; H 2 gas flow rate; iron doped indium oxide; thin film ABSTRAK Semikonduktor magnetik cair (DMSs) sentiasa menjadi tarikan utama untuk dikaji disebabkan penggunaannya yang meluas dalam spintronik. Kajian ini dijalankan untuk mengkaji kesan perbezaan aliran gas hidrogen sepuh lindap pada sifat fizikal filem Fe terdop indium oksida. Filem In 1.92 Fe 0.08 O 3 telah disediakan melalui kaedah sol-gel diikuti dengan teknik salutan putaran. Kadar aliran gas hidrogen yang berlainan digunakan semasa proses penyepuh lindapan. Kesemua sampel menunjukkan orientasi tinggi pada arah (222) dan berstruktur polihablur. Saiz butiran bertambah apabila kadar aliran bertambah disebabkan pengurangan H 2 . Kajian FTIR menunjukkan kewujudan ikatan O-H dalam julat 3000 -4000 cm -1 dan ia disebabkan oleh aliran gas H 2 semasa proses penyepuh lindapan. Kerintangan filem nipis In 1.92 Fe 0.08 O 3 menurun dan kepekatan pembawa meningkat dengan peningkatan kadar aliran . Kajian ini mempunyai keberertian pada sifat kebergantungan kepada saiz dan ikatan kimia dalam filem Fe terdop In 2 O 3 . Kata kunci: Fe terdop indium oksida; filem nipis; FTIR; kadar aliran gas H 2