How to make animation like this using array? How can I make animation like this using array without deforming the shape of the ball? I already tried to make it using array and curve but the balls are deforming when I make the 2nd layer of the curve.
(sorry for my bad english)
You don't need an array, what you need is a curve with the shape you want and then use dupliframes. 

To set it up read How can I duplicate a mesh along a curve? 

Then, animate the "duplication end" for the object used along the curve Read: How can i add more duplicates to a curve?