Along with a series of research works on the physical prototype and properties of the memory cell,an SPICE model for phase-change memory（PCM） simulations based on Verilog-A language is presented.By handling it with the heat distribution algorithm,threshold switching theory and the crystallization kinetic model,the proposed SPICE model can effectively reproduce the physical behaviors of the phase-change memory cell.In particular,it can emulate the cell＇s temperature curve and crystallinity profile during the programming process,which can enable us to clearly understand the PCM＇s working principle and program process.
An integrated phase change memory cell with dual trench epitaxial diode is successfully integrated in the traditional 0.13μm CMOS technology.By using dual trench isolated structure in the memory cell,it is feasible to employ a Si-diode as a selector for integration in a crossbar structure for high-density phase change memory even at 45 nm technology node and beyond.A cross-point memory selector with a large on/off current ratio is demonstrated,the diode provides nine orders of magnitude isolation between forward and reverse biases in the SET state.A low SET programming current of 0.7mA is achieved and RESET/SET resistance difference of 10000×is obtained.
