A phase change memory cell having a flat lower bottom electrode and a method for fabricating the same. The first input channel receives speech of a first user, and the second input channel receives speech of a second user. The weight applied to the surface by the grinding head assembly may be varied from the weight of the grinding head assembly to zero. A disparity change between a disparity value determined for a static region of a current image and a motion compensated disparity value of a previous image is determined.