Effect of tilted angle in trench structure on phase change memory operation using TCAD simulation

As the devices have faced the limit of shrinking, a lot of candidates rise to lead the next generation of device technology. One of the well-known candidates is a phase change memory (PCM) which is based on a chalcogenide material, called Ge₂Sb₂Te₅ (GST). Principle of PCM operation is decided by changing the phase of GST thermodynamically. Thus, structures of a PCM cell such as keyhole and μ-trench are mainly used for Joule heating. However, in the process of making a trench, there is inevitably a difference between top and bottom aperture of the trench, which affects the electrical properties of PCM. In this study, we build a PCM cell structure using technology computer-aided design (TCAD) and analyze the effect of a tilted angle of the trench on the phase change memory operation.