Please see attached SEM image

Left image is my PZT film and right image film is PZT film that I want to make

1. Some voids(black circled) is formed in my film. But there are no voids in right film. How solve this problem?

2. Small grain like shape(yellow circled) is formed in my film. But I think that enough heat is applied in my film during crystallization(650~700 degree C)

3. There are not layer separation in right film though it is consisted of multi layer film. But my film has separated layer(in white box). How to remove it?

During forming film, condition that I performed is like below

bottom electrode : Au 

solution : commercial PZT 0.7M

spin coating : 3000rpm, 30s

pyrolysis : 450 degree C, 5min (each layer on hot plate)

pre-annealing : 650~700 degree C, 10min (every four layers in box furnace(air))

final-annealing : 650~700 degree C, 40min (in box furnace(air))

Can you point out the problems in my experiments or give me some tips for sol-gel derived PZT film?

Thank you!