What is causing the ghost touch?

Hi,is anybody figure it out yet what is causing the ghost touch?i have a iPad mini,I replaced the screen digitizer,I put electrical tape around the digitizer but still not working.

If I lift the screen up with out touching the lcd it's fine,I don't see the ghost touch but if I try to closed the screen and press down the ghost touch appears again,please anybody had this issue before I will appreciate your help.