Coating a glass monocapillary x-ray optics with high-density film is a promising way to improve transmission characteristics. For a long time, it has been a challenge to coat a high-density film in the inside of monoc...Coating a glass monocapillary x-ray optics with high-density film is a promising way to improve transmission characteristics. For a long time, it has been a challenge to coat a high-density film in the inside of monocapillary with an extremely high length-to-diameter ratio. In this work, Hf O2 film is deposited on the inner wall of a tapered glass monocapillary with length 9.9 cm, entrance diameter 596.4 μm, and exit diameter 402.3 μm by atomic layer deposition. The coated and uncoated monocapillaries are studied by the transmission process of x-rays with energy from 5 ke V to 100 ke V and the x-ray fluorescence(XRF) spectra of a Mo sample are detected. Improved transmission characteristics have been obtained for the Hf O2-coated monocapillary. The energy upper limit of focused x-rays increases from 18.1 ke V to 33.0 ke V and the ‘penetration halo’ is suppressed to some extent. The XRF spectrum presents two stronger peaks at ~ 17.4 ke V and~ 19.6 ke V which are considered as the characteristic x-rays of Mo Kα and Mo Kβ. These results reveal that more higher energy x-rays from the W x-ray tube are totally reflected on the inner wall of the Hf O2-coated glass monocapillary due to the increase of total reflection critical angle. This work is significant for more applications of monocapillary in higher energy x-ray field.展开更多
We develop a novel and convenient method to prepare large area single-layer and multi-layer graphene through surface modification with oxygen plasma.The obtained large area single-layer graphene is dozens of microns w...We develop a novel and convenient method to prepare large area single-layer and multi-layer graphene through surface modification with oxygen plasma.The obtained large area single-layer graphene is dozens of microns wide in the lateral dimension and characterized by optical microscopy,atomic force microscopy.Raman spectroscopy show multilayer graphene has less disorder density than single-layer graphene.X-ray photoelectron spectroscopy（XPS） analysis shows that hydroxyl groups are formed on the HOPG surface during oxygen plasma pre-treatment.Hydrogen bonds develop between hydroxyl groups on HOPG surface and silanol groups on hydroxylated SiO_2/Si substrate,which facilitate the transfer process.This study may provide a potential approach to develop graphene-based devices by using the large area lithographic printing process.展开更多
基金the National Key Research and Development Program of China(Grant No.2018YFF0109100)Fund from the Institute of Electrical Engineering,Chinese Academy of Sciences(Grant No.E1554404)the National Natural Science Foundation of China(Grant Nos.11675019 and 11875087).
文摘Coating a glass monocapillary x-ray optics with high-density film is a promising way to improve transmission characteristics. For a long time, it has been a challenge to coat a high-density film in the inside of monocapillary with an extremely high length-to-diameter ratio. In this work, Hf O2 film is deposited on the inner wall of a tapered glass monocapillary with length 9.9 cm, entrance diameter 596.4 μm, and exit diameter 402.3 μm by atomic layer deposition. The coated and uncoated monocapillaries are studied by the transmission process of x-rays with energy from 5 ke V to 100 ke V and the x-ray fluorescence(XRF) spectra of a Mo sample are detected. Improved transmission characteristics have been obtained for the Hf O2-coated monocapillary. The energy upper limit of focused x-rays increases from 18.1 ke V to 33.0 ke V and the ‘penetration halo’ is suppressed to some extent. The XRF spectrum presents two stronger peaks at ~ 17.4 ke V and~ 19.6 ke V which are considered as the characteristic x-rays of Mo Kα and Mo Kβ. These results reveal that more higher energy x-rays from the W x-ray tube are totally reflected on the inner wall of the Hf O2-coated glass monocapillary due to the increase of total reflection critical angle. This work is significant for more applications of monocapillary in higher energy x-ray field.
基金Project supported by the Opening Project of Key Laboratory of Microelectronics Devices & Integrated Technology,Institute of Microelectronics, Chinese Academy of Sciences
文摘We develop a novel and convenient method to prepare large area single-layer and multi-layer graphene through surface modification with oxygen plasma.The obtained large area single-layer graphene is dozens of microns wide in the lateral dimension and characterized by optical microscopy,atomic force microscopy.Raman spectroscopy show multilayer graphene has less disorder density than single-layer graphene.X-ray photoelectron spectroscopy（XPS） analysis shows that hydroxyl groups are formed on the HOPG surface during oxygen plasma pre-treatment.Hydrogen bonds develop between hydroxyl groups on HOPG surface and silanol groups on hydroxylated SiO_2/Si substrate,which facilitate the transfer process.This study may provide a potential approach to develop graphene-based devices by using the large area lithographic printing process.
