Effects of Temperature, Target/Substrate Distance, and Background Pressure on Growth of ZnO Nanorods by Pulsed Laser Deposition

Abstract

The growth of ZnO nanorods on the c-plane of Al2O3 substrates by PLD was been investigated by controlling processing conditions such as growth temperature, distance between target and substrate, and background oxygen pressure. ZnO nanorods were observed from the growth temperature of 600 degrees C for the oxygen pressure of 30 mTorr and the target/substrate distance of 70 mm. The diameters of the ZnO nanorods at the temperature of 700 degrees C and the oxygen pressure of 30 mTorr were approximately 200, 70, and 40 nm for the distance of 45, 70, and 100 mm, respectively. ZnO films without nanorods were observed at the distance of 70 mm and the temperature of 700 degrees C when the oxygen pressure decreased to 1 mTorr. The kinetic energy of the ablated particles by the laser decreases during collisions with background oxygen molecules, resulting in conditions that favor the growth of ZnO nanorods.

Low-Temperature PLD-Growth of Ultrathin ZnO Nanowires by Using Zn x Al1−x O and Zn x Ga1−x O Seed Layers

“…The SEM images for all doping concentrations and temperatures are shown in the Additional file 1 : Figure S1 and Additional file 2 : Figure S2. For the growth on the pure ZnO seed layer, a low density of vertically oriented NWs is obtained at T =950 ∘ C as expected from previous results [ 16 , 23 ]. For the seed layers used here, we obtained NWs with a diameter of about 70 nm and an aspect ratio of about 25.…”

“…For the seed layers used here, we obtained NWs with a diameter of about 70 nm and an aspect ratio of about 25. Note, it is also possible to fabricate NWs with larger diameters up to 600 nm [ 23 – 25 ]. By reducing the growth temperature down to T ≈700 ∘ C, the diameter of the NWs decreases to 16 nm and the aspect ratio increases up to 300.…”

Effect of substrate temperature on structural and magnetic properties of c-axis oriented spinel ferrite Ni0.65Zn0.35Fe2O4 (NZFO) thin films

“…As a result, the mean free path of the ablated particles might increase. So higher temperatures contribute to the synthesis of high quality crystalline thin films by increasing surface mobility of adatoms [21][22][23], [27] . The increases of crystalline quality with increase of the substrate temperature of the films are evident from the increase of the XRD peak intensities as shown in Fig.1..…”

“…Many attempts have been made to grow high-quality spinel ferrite thin films by different techniques such as molecular beam epitaxy (MBE), rf sputtering, pulsed laser deposition (PLD), spin-spray, sol-gel, electrochemical deposition, direct liquid phase precipitation and hydrothermal growth [13], [21][22][23][24][25][26]. The structural and magnetic properties of NZFO are strongly dependent on growth parameters, such as substrate temperature, oxygen partial pressure, substrate to target distance, laser fluence etc [13], [27]. Among all the growth parameters, substrate temperature plays a vital role during growth, but studies on effects of growth temperature on structural and magnetic properties of c-axis oriented NZFO thin films grown by PLD are limited.…”