Comparison of DC and RF Sputtered Zinc Oxide Films with Post-Annealing and Dry Etching and Effect on Crystal Composition

Abstract

Zinc oxide (ZnO) thin films were deposited on Silicon substrates by DC and RF sputtering deposition. Thermal annealing was performed at up to 900°C in N2 for 30 min. The samples were dry etched for 30 min using CHF3 plasma. The effect of different sputtering techniques, annealing and reactive ion etching (RIE) were investigated using X-ray diffraction, Rutherford backscattering (RBS), photoluminescence (PL) spectra, atomic force microscopy (AFM), scanning electron microscopy (SEM), and piezoelectric measurements. The PL response improved considerably during annealing and was further enhanced after RIE process. RBS traced a C rich surface layer on all etched samples, which is possibly caused by the etching gas.

Piezoelectric Materials for Energy Harvesting and Sensing Applications: Roadmap for Future Smart Materials

“…[ 99 ] The mean value of the d 33 coefficient measured over many individual NRs was 11.8 pC N –1 , which is ≈18% higher than 9.93 pC N –1 measured for ZnO bulk material. [ 100 , 101 , 102 ] The d 33 value was higher by a factor ranging between 28–167%, compared to ZnO nanostructures synthesized by the aqueous chemical method, [ 103 ] hydrothermal, [ 104 ] and template‐assisted vapor deposition. [ 105 ]…”

ZnO Thin Films Growth Optimization for Piezoelectric Application

“…However, for sputter-deposited ZnO films, the typical d 33 values reported in the literature are of few pm/V [ 30 , 31 ], lower than those obtained in films grown with other techniques. Values are particularly low when radio frequency (RF) is employed, due to generally smaller grains [ 32 , 33 , 34 , 35 ]. These small grains can reduce the effective displacement if their polarizations are not fully aligned, and the presence of impurities at grain boundaries can generate a large number of free electrons inside their structure, reducing the final resistivity.…”

The effect of substrate temperature on filtered vacuum arc deposited zinc oxide and tin oxide thin films

“…Various deposition methods have been applied to deposit transparent and conducting ZnO and SnO 2 thin films, including spray pyrolysis [6,7], pulsed laser deposition (PLD) [8,9], magnetron sputtering [10][11][12], evaporation [13], reactive ion-assisted deposition [14] and filtered vacuum arc deposition (FVAD) [15][16][17][18][19][20][21][22]. The latter method was shown to produce dense and good adhering films on low-temperature substrate with higher deposition rate (up to 10 nm/s) [17].…”