Microstructural, crystal structure and electrical characteristics of shock-consolidated Ga2O3 doped ZnO bulk

Ga2O3 (5 wt.%) doped zinc oxide (ZnO, 95 wt.%) bulk was fabricated by underwater shock compaction technique. The microstructural, crystal structure and electrical properties of shock-consolidated samples were investigated and compared to a commercially available sintered Ga2O3 (5 wt.%) doped ZnO (95 wt.%). The relative density of shock-consolidated sample was about 97% of the theoretical density, and no grain growth and lattice defects were confirmed. The grain boundary resistance was remarkably higher than that of commercial sintered Ga2O3 doped ZnO and nonlinear current–voltage (I–V) characteristics of shock-consolidated ZnO and Ga2O3 doped ZnO were very lower than that of commercial ZnO varistor.

Graphical AbstractThis is a photograph of shock-consolidated Ga2O3 doped ZnO bulk using underwater shock compaction. The shock-consolidated Ga2O3 doped ZnO bulk was processed with an ellipse shape and its size is 30 mm diameter, 25 mm width and 4 mm thickness, and the relative density was about 97 % (5.48 g/cm3) of theoretical density (5.65 g/cm3).Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights► A Ga2O3 doped ZnO bulk was successfully fabricated by underwater shock compaction technique. ► The cracking problem in the shock-consolidated Ga2O3 doped ZnO bulk was not generated. ► The use of Cu powders was effective to remove the cracking problem. ► No grain growth and lattice defects were confirmed. ► The shock-consolidated Ga2O3 doped ZnO bulk exhibited high electric resistance compared with the commercial sintered Ga2O3 doped ZnO bulk.