Deposition and characterization of germanium nitride film using different thermal nitridation temperature / Low Yan Jie
Date of Award
7-1-2018
Thesis Type
masters
Document Type
Thesis (Restricted Access)
Divisions
eng
Department
Faculty of Engineering
Institution
University of Malaya
Abstract
This study is aimed at investigating the effect of thermal nitridation temperature on the growth of germanium nitride (?-Ge3N4) thin film and its effectiveness as a buffer layer to suppress the growth of unwanted germanium oxide (GeO2) interfacial layer. The ?-Ge3N4 films were grown on germanium substrate (Ge) by thermally nitriding Ge with nitrogen (N2) gas purging for 15 minutes at 400, 500 and 600°C. The temperature dependence of the growth of ?-Ge3N4 films under pure N2 gas purge was studied profoundly through X-ray diffraction (XRD) and Fourier transform infrared (FTIR) characterization. The physical, chemical and compositional properties of 400, 500 and 600°C thermally nitrided Ge samples were analyzed through the resulting XRD and FTIR spectra. The resulting XRD spectra give information on the intensity of ?-Ge3N4 and t-GeO2 phases, microstrain embedded in each phase, and crystallite size of the phases by means of Debye-Scherrer equation and Williamson-Hall (W-H) analysis. The intensities of ?-Ge3N4 phases were found to first increase from 400°C and reach a peak at 500°C, gradually declining thereafter at 600°C. This suggests that the optimum growth of ?-Ge3N4 phases is at 500°C as the ?-Ge3N4 phases are appeared to be unstable at 400 and 600°C. The ?-Ge3N4 was determined to exhibit the largest crystallite size and highly homogeneous size distribution at 500°C indicating the highly uniform growth rate at 500°C. Tensile microstrain embedded in ?-Ge3N4 layer was only observed at the highest growth rate temperature, 500°C. The tensile microstrain indicates the ?-Ge3N4 phase islands has grown into a uniform film by forming grain boundary. The compressive microstrain in 400 and 600°C ?-Ge3N4 layer was expected to be attributed to the disruption of ?-Ge3N4 thin film growth by formation of t-GeO2. Based on the FTIR results, the 500°C nitrided sample was found to have a substantial number of Ge-N characteristic peaks consecutively over the wavenumber range of 400 to 1300 cm-1 and a very small number of low intensity peaks which are indicative of Ge-O bond. Unlike 500°C nitrided sample, relatively high intensity peaks of Ge-O bond are observed in the spectra of 400 and 600°C nitrided samples. Broadly translated, the result findings indicate 500°C as the optimal thermal nitridation temperature of ?-Ge3N4 thin film growth.
Note
Dissertation (M.A.) - Faculty of Engineering, University of Malaya, 2018.
Recommended Citation
Low, Yan Jie, "Deposition and characterization of germanium nitride film using different thermal nitridation temperature / Low Yan Jie" (2018). Student Works (2010-2019). 5678.
https://knova.um.edu.my/student_works_2010s/5678