Hardness variations influenced the morphologies S. Balamurali1, R. Chandramohan2 S.Saravanakumar2 M.Karunakaran 3 and K. Sivakumar1
1.Hindusthan College of Engineering & Technology, Coimbatore - 641 032, India. 2. Annamalai Chettiar Research Centre, Sree Sevugan Annamalai College, Devakottai - 630303, India. 3.Alagappa Government Arts College, Karaikudi – 630 003, India. balamuraliphd82@gmail.com Abstract : Mn doped ZnO films were prepared by SILAR technique. These films were characterized by hardness study and Scanning Electron Microscope. The undoped ZnO film hardness decreased. The Mn atoms occupy the intersistial position. Due to this reason hardness were increased by heating. During the annealing the atoms were oriented in different direction. Based on the orientation it appeared as various morphologies (needle and Hone cone structure).
Fig 1. Hardness of Mn doped ZnO thin films annealed at RT, 3000C & 3500C for 30 minutes for the concentration of Mn 1 %, 2 % and 3 % for film with different number of dippings. Modified Experimental Arrangements The films were annealed at different Hardness of Temp Composition temperature with uniform interval. These 100 Dipping films were different thickness and RT 1 79 composition of the films. These films were exhibited the hexagonal 2 75 wurtzite. The films annealed at 350 0C the 3 70 hardness of the film increased and 0 300 C 1 65 saturated also. Due to the heating of films it adhere to the 2 62 substrate. The substrate and films having 3 63 very good bonding because of the uniform 0 350 C 1 84 heating and films having crystalline nature. Figure 2. Schematic 2 83 For this reason the film's hardness gradually representation of solution dip 3 85 increased based on temp and composition. technique The corresponding hardness of the films morphology were shown in fig 3 and fig 4. Those morphologies were flowery, honey cone, needle and chips structure. For these films hardness and the morphology of the films were good and these type of films were used in the various applications. Because the area of the few structure like flowery, needle and chips were high. For electrical application these morphologies can be used. Honey cone structure is used in the gas sensor application.
Figure 3. These films annealed at 3000C for 30 minutes for the concentration of Mn 1 %, 2 % and 3 % for film with different number of dippings.
Figure 4. These films annealed at 3500C for 30 minutes for the concentration of Mn 1 %, 2 % and 3 % for film with different number of dippings.
Conclusion: For 1% of Mn doped ZnO annealed at 350 0C comparatively shows increased hardness. The high hardness film shows the needle like structure. For electrical application these morphologies can be used.