I think the intensity of there peak because of the following

1-the intensity of 100 appears

because of The orientation of the substrate had some impact on the

Orientation of the deposited ZnO

2-the intensity of (002)

The mechanism of formation of the c-axis preferentially oriented ZnO thin film can be suggested that the value of the surface free energy is minimum for the ZnO (0 0 2) plane at the growth stage

3-I don’t Know about (101) peak intensity

Hi, Kakil

These 3 diffraction patterns arises from 3 different planes mentioned above. They have different d- spacing also. Do you want to study effect of Si doping on ZnO? If you want to understand about peaks and intensity read Elements Of X Ray Diffraction by B. D. Cullity, Its nice book!

Have a good day!

Dear Abdul Parchur

thank you for your help now i work on depostion ZnO/Si

ZnO thin films had three dominating characteristic

peaks at (1 0 0), (1 0 1) and (0 0 2)

Hi Kakil, Sounds good! ZnO has many patterns, however these 3 characteristic peaks among. If you have time read this http://mesa.ac.nz/wp-content/uploads/2011/07/02_basic-xrd.pdf. On how many factors intensity will depends and some fundamental information explained here.

In my opinion, The XRD peak intensities is determined by the crystal plane indices (hkl) and the reflected intensity of atom. Therefore, every polycrystal materials have itself PDF card for a random aligned powder, it is also means the peak intensities shuld be different for the different crystal plane at genarally case. Secondly, the peak intensities is also ralatied by the texture, especially for film materials, most materials have a texture, thus the peak intensities could deviate the standard PDF card. This method can also be used for determined the texture degree, espetialy for pernamant magnetic application.