One-step growth of structured ZnO thin films by chemical bath deposition in aqueous ammonia solution

Abstract

Structured ZnO films have been fabricated on soda-lime glass slides at a low temperature (80-85 • C) by a chemical bath deposition method in one step without seed layers. Mixed aqueous solutions of zinc sulfate, ammonia and thiourea were used at alkaline conditions. The influence of the ammonia concentration in the initial solution on the property of the deposited film was investigated systematically. The morphology, structural and optical properties of the deposited films were examined and characterized by x-ray diffraction (XRD), energy-dispersive spectroscopy x-ray diffraction (EDX), scanning electron microscopy (SEM), Raman spectroscopy and photoluminescence (PL) spectroscopy. Structural analyses with XRD, EDX and SEM revealed that the formed films exhibit a wurtzite hexagonal phase. The deposited film was more preferentially oriented in the (0 0 2) direction with an increase in the ammonia concentration from 0.75 to 2 mol l −1 . The optical-phonon E 2 mode at 437 cm −1 in the Raman spectrum, together with the XRD and EDX analyses, showed that flower-like and columnar crystalline ZnO films were formed in two ammonia concentration ranges, 0.75-1.4 mol l −1 and 1.6-2.0 mol l −1 , respectively. Furthermore, PL spectra showed strong and high intensity peaks of UV emission with suppressed green emission for these deposited ZnO films. ZnS films were formed with a high ammonia concentration of 3.0 M. The formation mechanisms of ZnO, Zn(OH) 2 and ZnS phases were discussed.

Chemically deposited PbSe thin films: factors deterring reproducibility in the early stages of growth

“…[1][2][3][4] However, irreproducibility is a common issue when approaching film growth via chemical bath deposition (CBD). 1,[5][6][7] This is true for many compounds grown through this technique but is generally not addressed. The root cause of irreproducibility is concealed in the various parameters affecting growth kinetics that are not always fully understood.…”

Unique surface textures of ZnO films deposited by chemical bath deposition

“…Using the CBD technique, a number of different structures of ZnO films have been previously reported such as nanowires or nanorods 1–4, nanoflowers 3–6, nanobelts 7, nanocolumns or nanoplates 8, nanotetrapod 9, nanotube 10, and nanosheets 11–14. In this study, we report unique textures of ZnO films grown by CBD.…”

Interface energy barrier tailoring the morphological structure evolution from ZnO nano/micro rod arrays to microcrystalline thin films by Mn doping

“…38 Further, the ower like morphology observed on soda-lime glass slide due to the crystallographic plane growth in the order of ( 1011) > (10 10) > ( 0002) and (0002) > ( 1010) > (10 11). 41 Xu et al have investigated stelliform like morphology on Au/glass substrate and this result clearly revealed that the crystallographic plane growth order is ( 1011) > (0002) > ( 1010) stimulating stelliform-like morphology. 42 Fig.…”