A method for fabricating a multi-layer phase change memory device includes forming a phase change memory layer including a plurality of phase change memory elements on a word line formed on a plurality of semiconductor devices on a first semiconductor substrate, each phase change element having a notch formed at an upper surface thereof, forming an access device layer including plurality of access devices on a second semiconductor substrate, each access device having a conductive bump formed thereon, and combining the first and second semiconductor substrates and slidably inserting and locking each conductive bump of the plurality of access devices into each notch of the plurality of phase change memory elements to electrically connect the access devices to the phase change memory elements.