Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse Irradiation
Element-doped phase change material (PCM) could improve the performances, e.g., better thermal stability, higher electrical resistance, and faster crystallization speed; thus, the influence of the doping element needs to be further investigated. In this paper, a femtosecond laser, which could realiz...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-12-01
|
| Series: | Micromachines |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-666X/13/12/2168 |
| _version_ | 1797456204609355776 |
|---|---|
| author | Hao Wu Xiaobin Zhang Weina Han |
| author_facet | Hao Wu Xiaobin Zhang Weina Han |
| author_sort | Hao Wu |
| collection | DOAJ |
| description | Element-doped phase change material (PCM) could improve the performances, e.g., better thermal stability, higher electrical resistance, and faster crystallization speed; thus, the influence of the doping element needs to be further investigated. In this paper, a femtosecond laser, which could realize the ultrafast phase transition rate of PCM between amorphization and crystallization, was used to explore the properties of nitrogen-doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> (GST), and a bond effect was proposed. The pure GST and different nitrogen contents of doped GST films were investigated by femtosecond laser pulse excitation through a pump–probe shadowgraph imaging technique. The results showed that the element-doped films could change photon absorption because of the increase in free carriers. This caused the faster rate of reflectivity to change in the irradiated area by the laser beam as the more nitrogen doped. When the nitrogen content increased, the crystallization evolution became harder because it enhanced the bond effect, which suppressed crystalline grain growth and improved the thermal stability. Based on the analysis in the paper, the desired performances of PCMs, e.g., ultrafast dynamics, crystallization evolution, and thermal stability, could be controlled according to the demands by modifying the bond effect. |
| first_indexed | 2024-03-09T16:04:57Z |
| format | Article |
| id | doaj.art-351896f5ac8e4091b23768ade09845b1 |
| institution | Directory Open Access Journal |
| issn | 2072-666X |
| language | English |
| last_indexed | 2024-03-09T16:04:57Z |
| publishDate | 2022-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Micromachines |
| spelling | doaj.art-351896f5ac8e4091b23768ade09845b12023-11-24T16:45:19ZengMDPI AGMicromachines2072-666X2022-12-011312216810.3390/mi13122168Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse IrradiationHao Wu0Xiaobin Zhang1Weina Han2Laser Micro/Nano-Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, ChinaLaser Micro/Nano-Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, ChinaLaser Micro/Nano-Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, ChinaElement-doped phase change material (PCM) could improve the performances, e.g., better thermal stability, higher electrical resistance, and faster crystallization speed; thus, the influence of the doping element needs to be further investigated. In this paper, a femtosecond laser, which could realize the ultrafast phase transition rate of PCM between amorphization and crystallization, was used to explore the properties of nitrogen-doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> (GST), and a bond effect was proposed. The pure GST and different nitrogen contents of doped GST films were investigated by femtosecond laser pulse excitation through a pump–probe shadowgraph imaging technique. The results showed that the element-doped films could change photon absorption because of the increase in free carriers. This caused the faster rate of reflectivity to change in the irradiated area by the laser beam as the more nitrogen doped. When the nitrogen content increased, the crystallization evolution became harder because it enhanced the bond effect, which suppressed crystalline grain growth and improved the thermal stability. Based on the analysis in the paper, the desired performances of PCMs, e.g., ultrafast dynamics, crystallization evolution, and thermal stability, could be controlled according to the demands by modifying the bond effect.https://www.mdpi.com/2072-666X/13/12/2168nitrogen doped GSTtemporal-spatial-resolved dynamicsfemtosecond laser excitationphase transition evolutiona bond effect |
| spellingShingle | Hao Wu Xiaobin Zhang Weina Han Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse Irradiation Micromachines nitrogen doped GST temporal-spatial-resolved dynamics femtosecond laser excitation phase transition evolution a bond effect |
| title | Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse Irradiation |
| title_full | Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse Irradiation |
| title_fullStr | Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse Irradiation |
| title_full_unstemmed | Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse Irradiation |
| title_short | Ultrafast Temporal-Spatial Dynamics of Phase Transition in N-Doped Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> Film Induced by Femtosecond Laser Pulse Irradiation |
| title_sort | ultrafast temporal spatial dynamics of phase transition in n doped ge sub 2 sub sb sub 2 sub te sub 5 sub film induced by femtosecond laser pulse irradiation |
| topic | nitrogen doped GST temporal-spatial-resolved dynamics femtosecond laser excitation phase transition evolution a bond effect |
| url | https://www.mdpi.com/2072-666X/13/12/2168 |
| work_keys_str_mv | AT haowu ultrafasttemporalspatialdynamicsofphasetransitioninndopedgesub2subsbsub2subtesub5subfilminducedbyfemtosecondlaserpulseirradiation AT xiaobinzhang ultrafasttemporalspatialdynamicsofphasetransitioninndopedgesub2subsbsub2subtesub5subfilminducedbyfemtosecondlaserpulseirradiation AT weinahan ultrafasttemporalspatialdynamicsofphasetransitioninndopedgesub2subsbsub2subtesub5subfilminducedbyfemtosecondlaserpulseirradiation |