2θ position of the (002) peak, grain size, I002 intensity ratio, and surface roughness of ZnO:B films deposited with various (100 − x)ZnO–xB2O3 targets. The grain size is calculated from the
broadening of the XRD peaks using the Scherrer equation. The I002 intensity ratio is defined as the I002 intensity divided by the sum of intensity of all diffraction peaks (I100 + I002+ I101+ I004).
The surface roughness is identified by AFM