TY - JOUR
T1 - Exploring the effects of graphene and temperature in reducing electron beam damage
T2 - A TEM and electron diffraction-based quantitative study on Lead Phthalocyanine (PbPc) crystals
AU - Jain, Noopur
AU - Hao, Yansong
AU - Parekh, Urvi
AU - Kaltenegger, Martin
AU - Pedrazo-Tardajos, Adrián
AU - Lazzaroni, Roberto
AU - Resel, Roland
AU - Geerts, Yves Henri
AU - Bals, Sara
AU - Van Aert, Sandra
N1 - Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/6
Y1 - 2023/6
N2 - High-resolution transmission electron microscopy (TEM) of organic crystals, such as Lead Phthalocyanine (PbPc), is very challenging since these materials are prone to electron beam damage leading to the breakdown of the crystal structure during investigation. Quantification of the damage is imperative to enable high-resolution imaging of PbPc crystals with minimum structural changes. In this work, we performed a detailed electron diffraction study to quantitatively measure degradation of PbPc crystals upon electron beam irradiation. Our study is based on the quantification of the fading intensity of the spots in the electron diffraction patterns. At various incident dose rates (e/Å2/s) and acceleration voltages, we experimentally extracted the decay rate (1/s), which directly correlates with the rate of beam damage. In this manner, a value for the critical dose (e/Å2) could be determined, which can be used as a measure to quantify beam damage. Using the same methodology, we explored the influence of cryogenic temperatures, graphene TEM substrates, and graphene encapsulation in prolonging the lifetime of the PbPc crystal structure during TEM investigation. The knowledge obtained by diffraction experiments is then translated to real space high-resolution TEM imaging of PbPc.
AB - High-resolution transmission electron microscopy (TEM) of organic crystals, such as Lead Phthalocyanine (PbPc), is very challenging since these materials are prone to electron beam damage leading to the breakdown of the crystal structure during investigation. Quantification of the damage is imperative to enable high-resolution imaging of PbPc crystals with minimum structural changes. In this work, we performed a detailed electron diffraction study to quantitatively measure degradation of PbPc crystals upon electron beam irradiation. Our study is based on the quantification of the fading intensity of the spots in the electron diffraction patterns. At various incident dose rates (e/Å2/s) and acceleration voltages, we experimentally extracted the decay rate (1/s), which directly correlates with the rate of beam damage. In this manner, a value for the critical dose (e/Å2) could be determined, which can be used as a measure to quantify beam damage. Using the same methodology, we explored the influence of cryogenic temperatures, graphene TEM substrates, and graphene encapsulation in prolonging the lifetime of the PbPc crystal structure during TEM investigation. The knowledge obtained by diffraction experiments is then translated to real space high-resolution TEM imaging of PbPc.
KW - Cryogenic temperature
KW - Electron beam damage
KW - Electron diffraction
KW - Graphene
KW - Lead Phthalocyanine
KW - Organic crystals
UR - http://www.scopus.com/inward/record.url?scp=85150810246&partnerID=8YFLogxK
U2 - 10.1016/j.micron.2023.103444
DO - 10.1016/j.micron.2023.103444
M3 - Article
AN - SCOPUS:85150810246
SN - 0968-4328
VL - 169
JO - Micron
JF - Micron
M1 - 103444
ER -