Crystallization of ion amorphized Ge2Sb2Te5 in nano-structured thin films

2010 ◽  
Vol 1251 ◽  
Author(s):  
Antonio Massimiliano Mio ◽  
Egidio Carria ◽  
Riccardo De Bastiani ◽  
Maria Miritello ◽  
Corrado Bongiorno ◽  
...  

AbstractThe crystallization kinetics of nano-structured amorphous Ge2Sb2Te5 (GST) regions (20-100 nm in diameter) obtained by Electron Beam Lithography (EBL) and 40 KeV Ge+ 1014/cm2 ion irradiation of crystalline 20 nm thick films was investigated. The amorphous regions, surrounded by crystalline cubic (fcc) or hexagonal (hcp) phase, were recrystallized by isothermal annealing in the temperature range 80°C - 120°C and by focused electron beam irradiation. The process was followed in situ by transmission electron microscope (TEM). The recrystallization is governed by the growth of the surrounding f.c.c. crystalline interface with a velocity of 2×10-2 nm/s at 110°C. The interface velocity is higher in the h.c.p. substrate less than a factor ten. Local focused electron beam irradiation induces instead crystalline nucleation inside the nano amorphous regions. Similar experiments have been performed on planar ion amorphized thin films lying on both GST crystalline phases. In both cases the recrystallization is mainly associated to the movement of the amorphous-crystalline interface. These results indicate that the stability of the amorphous region, generated by ion irradiation, is severely affected by the adjacent crystalline structure and by the size of the amorphous area, critically involved in the scaling of the PCM-based devices.

2018 ◽  
Vol 5 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Pradeep Singh ◽  
B R Venugopal ◽  
D R Nandini

Electron energy loss spectroscopy (EELS) in combination with transmission electron microscopy (TEM) is widely used for chemical state analysis of variety of chemical compounds. High beam sensitivity of substances like polymers hinders the possibility of exploring in-depth analysis provided through the high spatially resolved EELS spectroscopy. In this study, the electron beam irradiation damage on polymers were analyzed with varying dose of electron beams. The stability of the polymers under electron beam exposure depends on the chemical structure on the polymers. In this study the polymers with and without phenyl groups namely Polycarbonate, Polyethylene terephthalate, Polystyrene, Styrene Maleic Anhydride and Polymethylmethacrylate are selected for the comparative degradation study. Effect of varying the electron dose on the stability of polymers were monitored by recording the low-loss EELS spectrum in π to π* transition and (π+σ) to (π+σ)* transition region.


Author(s):  
B. L. Armbruster ◽  
B. Kraus ◽  
M. Pan

One goal in electron microscopy of biological specimens is to improve the quality of data to equal the resolution capabilities of modem transmission electron microscopes. Radiation damage and beam- induced movement caused by charging of the sample, low image contrast at high resolution, and sensitivity to external vibration and drift in side entry specimen holders limit the effective resolution one can achieve. Several methods have been developed to address these limitations: cryomethods are widely employed to preserve and stabilize specimens against some of the adverse effects of the vacuum and electron beam irradiation, spot-scan imaging reduces charging and associated beam-induced movement, and energy-filtered imaging removes the “fog” caused by inelastic scattering of electrons which is particularly pronounced in thick specimens.Although most cryoholders can easily achieve a 3.4Å resolution specification, information perpendicular to the goniometer axis may be degraded due to vibration. Absolute drift after mechanical and thermal equilibration as well as drift after movement of a holder may cause loss of resolution in any direction.


1999 ◽  
Vol 584 ◽  
Author(s):  
A. P. G. Robinson ◽  
R. E. Palmer ◽  
T. Tada ◽  
T. Kanayama ◽  
E. J. Shelley ◽  
...  

AbstractWe report systematic studies of the response of C60 derivatives to electron beam irradiation. Films of fourteen different mono, tris and tetra adduct methanofullerene C60 derivatives were produced by spin coating on hydrogen terminated silicon substrates. Exposure of the films to a 20 keV electron beam substantially altered the dissolution rate of the derivative films in organic solvents such as monochlorobenzene. All of the derivatives exhibited negative tone resist behaviour with sensitivities between ∼ 8.5 × 10-4 and ∼ 4 × 10-3 C/cm2 107, much higher than that of C60. Features with widths of ∼ 20 nm were produced using these compounds, and the etch ratios of the compounds were found to be more than twice those of a standard novolac based resist (SAL601).


2017 ◽  
Vol 1 (2) ◽  
Author(s):  
Q. Q. Lan ◽  
X. J. Zhang ◽  
X. Shen ◽  
H. W. Yang ◽  
H. R. Zhang ◽  
...  

2021 ◽  
Author(s):  
Seunghwan Lee ◽  
GeonHo Baek ◽  
Hye-mi Kim ◽  
Yong-Hwan Kim ◽  
Jin-Seong Park

Metalcone films can be rearranged from amorphous structures to 2D-like carbon by electron beam irradiation. The irradiated indicone (HQ) film can be used as an inhibitor for selective deposition delaying 20 cycles of ALD of ZnO.


Nanoscale ◽  
2018 ◽  
Vol 10 (17) ◽  
pp. 7978-7983 ◽  
Author(s):  
Liang Cheng ◽  
Xianfang Zhu ◽  
Jiangbin Su

The coalescence of two single-crystalline Au nanoparticles on surface of amorphous SiOxnanowire, as induced by electron beam irradiation, wasin situstudied at room temperature in a transmission electron microscope.


2005 ◽  
Vol 900 ◽  
Author(s):  
Tomoki Akita ◽  
Koji Tanaka ◽  
Masanori Kohyama ◽  
Masatake Haruta

ABSTRACTThe structure of Au nano-particles supported on CeO2 was investigated by using an analytical transmission electron microscope (TEM). The shape change of Au particles was observed during TEM observation, such as shrinking down to a mono-atomic layer on the CeO2 substrate. The electron beam irradiation experiment revealed that the shape change of Au particles is concerning with the oxidation state or the density of oxygen vacancies of CeO2 substrate where the rapid desorption and adsorption of oxygen occurs. It was also found that the reduction by strong electron beam irradiation and subsequent oxidation generate the decoration of Au particles by cerium oxide.


2014 ◽  
Vol 53 (11) ◽  
pp. 115502 ◽  
Author(s):  
Takuya Hirohashi ◽  
Kenichi Okazaki ◽  
Shunpei Yamazaki

Sign in / Sign up

Export Citation Format

Share Document