To study the short circuiting effects in the AlN thin film sensors
due to the crack formation at the step edge, we fabricated sensor
units on different underlying materials such as thermally (dry oxidation
at ∼900 ◦C) grown SiO2 (300 nm) on the Si wafers, native
oxide on the Si wafers, and Al2O3 deposited on the Si wafers by
e-beam evaporation (the temperature at the wafer