I encounter this kind of problem too to my 5s. I have done hard reset, soft reset and erase all setting but nothing of the method works. I've thought this is cause by the latest update 9.3.2 but it was not. I keep on reading some help from this forum too and have a try. The electric static cause by the lcd body and the cable and cause the ghost appear to the screen. I open the lcd and put some paper on the lcd cover and the cable too. Its help and the ghost gone. Still working properly now but not sure later.