| AVS 55th International Symposium & Exhibition | |
| Nanomanufacturing Focus Topic | Thursday Sessions |
| Session NM-ThP |
| Session: | Nanomanufacturing Poster Session |
| Presenter: | S.-K. Kang, Sungkyun Advanced Institute of Nano Technology (SAINT), Korea |
| Authors: | S.-K. Kang, Sungkyun Advanced Institute of Nano Technology (SAINT), Korea B.J. Park, Sungkyunkwan University, Korea S.W. Kim, Sungkyunkwan University, Korea T.H. Min, Sungkyunkwan University, Korea G.Y. Yeom, Sungkyun Advanced Institute of Nano Technology (SAINT), Korea |
| Correspondent: | Click to Email |
Phase-change random access memory (PRAM) has made a prominent progress in memory performance and has brought a bright prospect for the next generation nonvolatile memory technologies due to its excellent advantages. One of the chalcogenide-based phase-change materials that have been paid attention for nanoscale nonvolatile memories is Ge2Sb2Te5 (GST) which has advantageous properties such as high-speed phase transformation and high degree of read-write cyclability without any compositional change between different phases. Ge-Sb-Te based materials are known to be form halogenations easily and apt to be damaged when exposed to plasma in the etch process. In this work, we present X-ray photoelectron spectroscopy (XPS) data obtained from the surface of blank GST and etched GST features after etching in the halogen inductively coupled plasmas (ICP) such as CF4, Cl2 and HBr to investigate the extent of halogenation damage. And we also investigated surface damage of the GST etched by halogen-based neutral beam to compare with ICP process. Recently, the neutral beam etching (NBE) method is used by several researchers to avoid the charge-related damage. The damage related to charging can be eliminated because, compared to the conventional reactive ion etching, no ions participate in the etch process. Our neutral beam was formed using a low angle forward reflection of a parallel ion beam obtained by an ion gun. The XPS compositional depth profiling for the blank GST and the topological XPS analysis for the patterned GST were investigated after etching in the ICP and the NBE system to prove less damage process condition. In the etching of GST in halogen-based ICP and NBE system, the spectra of Ge, Sb and Te are shifted to higher binding energy region with different extents for different halogen-based plasmas. It indicates that GST film received different extent of damage for the halogen-based plasmas. Significantly, we could observe the less changes of GST-degradation when the NBE was applied to etch the GST.