Lead-free KNN-based thin films obtained by pulsed laser deposition

Abstract

In thiswork, 0.96(K0.48Na0.52)0.95Li0.05Nb0.94Sb0.06O3-0.04Ba0.94Ca0.06ZrO3 (KNLNS-BCZ) and 0.98(K0.48Na0.52)0.95Li0.05Nb0.95Sb0.05O3-0.02Ba0.5(Bi0.5Na0.5)0.5ZrO3 (KNLNS-BBNZ) ferroelectric thin films were obtained by pulsed laser deposition. The structural, and morphological characteristics were studied to determine the best deposition parameters and analyse the piezoelectric properties. The studied deposition parameters were temperature, laser fluence, oxygen partial pressure and frequency. These parameters impact important characteristics of the thin films like grain morphology, thickness, and roughness. KNLNS-BCZ thin films with pure perovskite structure, homogeneous grain growth, and thickness ≥100 nm were fabricated at 700 °C, 2 J/cm 2 , 300 mTorr, and frequencies of 5 Hz and 10 Hz. These films presented good ferroelectric behaviour and piezoelectric coefficient d33eff of 83.80 pm/V and 25.80 pm/V, respectively.

A Review of Piezoelectric Energy Harvesting: Materials, Design, and Readout Circuits

“…Due to the environmental and human health consequences of using lead-based materials [69], research has focused on the development of lead-free piezoelectric materials. Potassium sodium niobate (KNN) [70][71][72] exhibits a low piezoelectric constant, but its performance can be improved and made closer to that of PZT by modifying its structure through reactive patterned grain growth (RTGG) methods [73][74][75][76]. Its goal is to deliver piezoelectric characteristics without the environmental disadvantages associated with lead-based materials.…”