A phase change memory cell may be formed with a pair of chalcogenide phase change layers that are separated by a breakdown layer. The breakdown layer may be broken down prior to use of the memory so that a conductive breakdown point is defined within the breakdown layer. In some cases, the breakdown point may be well isolated from the surrounding atmosphere, reducing heat losses and decreasing current consumption. In addition, in some cases, the breakdown point may be well isolated from overlying and underlying electrodes, reducing issues related to contamination. The breakdown point may be placed between a pair of chalcogenide layers with the electrodes outbound of the two chalcogenide layers.