Investigation and solution of low yield problem for phase change memory with lateral fully-confined structure

This paper mainly focuses on solving the low yield problem for lateral phase change random access memory with a fully confined phase change material node. Improper over-etching and bad step-coverage of physical vapor deposition were the main reasons for the poor contact quality, which leads to the low yield problem. Process improvement was carried out to better control over-etching within 10 nm. Atomic layer deposition process was used to replace physical vapor deposition to guarantee good step coverage. Contrasting cross-sectional photos taken by scanning electron microscopy showed great improvement in contact quality. The atom layer deposition process was demonstrated to have good prospects in nano-contact for phase change memory application.

[1]  Eric Pop,et al.  Low-Power Switching of Phase-Change Materials with Carbon Nanotube Electrodes , 2011, Science.

[2]  M. Meyyappan,et al.  Indium selenide nanowire phase-change memory , 2007 .

[3]  S. Lai,et al.  Current status of the phase change memory and its future , 2003, IEEE International Electron Devices Meeting 2003.

[4]  Sumio Hosaka,et al.  A Novel Lateral Phase-Change Random Access Memory Characterized by Ultra Low Reset Current and Power Consumption , 2006 .

[5]  Qian Wang,et al.  Miniature organic transistors with carbon nanotubes as quasi-one-dimensional electrodes. , 2004, Journal of the American Chemical Society.

[6]  You Yin,et al.  Multilevel Storage in Lateral Top-Heater Phase-Change Memory , 2008, IEEE Electron Device Letters.

[7]  Yeonwoong Jung,et al.  High-resolution transmission electron microscopy study of electrically-driven reversible phase change in ge2sb2te5 nanowires. , 2011, Nano letters.

[8]  Sumio Hosaka,et al.  Lateral SbTeN based multi-layer phase change memory for multi-state storage , 2007 .

[9]  Xiaodong Wang,et al.  High quality metal-quantum dot-metal structure fabricated with a highly compatible self-aligned process* , 2015 .

[10]  D. Ielmini,et al.  Self-aligned nanotube-nanowire phase change memory. , 2013, Nano letters.

[11]  Luping Shi,et al.  GeTe/Sb7Te3 superlatticelike structure for lateral phase change memory , 2009 .

[12]  S. Ovshinsky.  Reversible Electrical Switching Phenomena in Disordered Structures , 1968 .

[13]  F. Merget,et al.  Lateral phase change random access memory cell design for low power operation , 2006 .

[14]  Soon-Gil Yoon,et al.  Phase-change InSbTe nanowires grown in situ at low temperature by metal-organic chemical vapor deposition. , 2010, Nano letters.