0000000000148236
AUTHOR
G. Schoenhense
Space-, time- and spin-resolved photoemission
Journal of electron spectroscopy and related phenomena 200, 94 - 118 (2015). doi:10.1016/j.elspec.2015.05.016
Inspection of EUVL mask blank defects and patterned masks using EUV photoemission electron microscopy
We report on recent developments of an "at-wavelength" full-field imaging technique for inspection of multilayer mask blank defects and patterned mask samples for extreme ultraviolet lithography (EUVL) by EUV photoemission electron microscopy (EUV-PEEM). A bump-type line defect with a width of approximately 35nm that is buried beneath Mo/Si multilayer has been detected clearly, and first inspection results obtained from a patterned TaN absorber EUVL mask sample is reported. Different image contrast of a similar width of multilayer-covered substrate line defect and on top TaN absorber square has been observed in the EUV-PEEM images, and origin of the difference in their EUV-PEEM image contra…
<title>Miniaturized objective lens for a photoelectron emission microscope</title>
Photoemission electron microscopy (PEEM) has turned out to be one of the most promising methods for surface analysis in the recent years. It is a full field imaging technique based on the emission of secondary electrons by far ultraviolet light or X-rays. The emission intensity of secondary electrons is critically dependent upon the acceptance angle of the incident radiation. However, the size of the microscope restricts this angle substantially. Miniaturizing the objective lens of the microscope reduces the restriction of the acceptance angle and improves the performance of the PEEM considerably. We report on the fabrication of a miniaturized objective lens containing the extraction electr…
Progress in HAXPES performance combining full-field k-imaging with time-of-flight recording
Journal of synchrotron radiation 26(6), 1996-2012 (2019). doi:10.1107/S1600577519012773
Actinic inspection of sub-50 nm EUV mask blank defects
A new actinic mask inspection technology to probe nano-scaled defects buried underneath a Mo/Si multilayer reflection coating of an Extreme Ultraviolet Lithography mask blank has been implemented using EUV Photoemission Electron Microscopy (EUV-PEEM). EUV PEEM images of programmed defect structures of various lateral and vertical sizes recorded at around 13 nm wavelength show that 35 nm wide and 4 nm high buried line defects are clearly detectable. The imaging technique proves to be sensitive to small phase jumps enhancing the visibility of the edges of the phase defects which is explained in terms of a standing wave enhanced image contrast at resonant EUV illumination.
At-wavelength inspection of sub-40 nm defects in extreme ultraviolet lithography mask blank by photoemission electron microscopy.
A new at-wavelength inspection technology to probe nanoscale defects buried underneath Mo/Si multilayers on an extreme ultraviolet (EUV) lithography mask blank has been implemented using EUV photoemission electron microscopy (EUV-PEEM). EUV-PEEM images of programmed defect structures of various lateral and vertical sizes recorded at an ~13.5 nm wavelength show that 35 nm wide and 4 nm high buried line defects are clearly detectable. The imaging technique proves to be sensitive to small phase jumps, enhancing the edge visibility of the phase defects, which is explained in terms of a standing wave enhanced image contrast at resonant EUV illumination.
Exchange coupling in the correlated electronic states of amorphous GdFe films
The bulk sensitivity of hard x-ray photoelectron spectroscopy in combination with circularly polarized radiation of the P09 beamline at PETRA III enables the investigation of the magnetic properties of capped films. We have determined the temperature dependence of the magnetic circular dichroism in the Fe 2$p$ and in the Gd 3$d$ states in amorphous GdFe films. The magnetic dichroism reflects the stronger temperature dependence of Gd moments compared to Fe moments in agreement with mean-field models. We resolved the exchange split Gd 3${d}_{5/2}$ substates and found a significant temperature dependence of the splitting which is attributed to a temperature dependent part of the exchange energ…
Actinic EUVL mask blank defect inspection by EUV photoelectron microscopy
A new method for the actinic at-wavelength inspection of defects inside and ontop of Extreme Ultraviolet Lithography (EUVL) multilayer-coated mask blanks is presented. The experimental technique is based on PhotoElectron Emission Microscopy (PEEM) supported by the generation of a standing wave field inside and above the multilayer mask blank when illuminated near the resonance Bragg wavelength at around 13.5 nm wavelength. Experimental results on programmed defect samples based on e-beam lithographic structures or PSL equivalent silica balls overcoated with an EUV multilayer show that buried defects scaling down to 50 nm in lateral size are detectable with further scalability down to 30 nm …
Photoemission microscopy with microspot-XPS by use of undulator radiation and a high-throughput multilayer monochromator at BESSY
We present a new experiment for photoelectron microspectroscopy by use of undulator radiation, which has been set up at the beamline U2 at the Berlin electron storage ring BESSY 1. This approach employs a non-imaging simulated hemispherical electron energy analyser attached to an imaging photoemission electron microscope (FOCUS IS-PEEM) with integrated microarea selector. The photoemission microscope exhibits a lateral resolution of 25 nm (with 4.9 eV UV-excitation), while the resolution with incident synchrotron radiation in the soft X-ray range is about 100-120 nm (mainly due to chromatic aberrations). Photoemission microscopy as well as photoelectron microspectroscopy of selected areas o…
Low vacuum photo electron emitting thin films
Impact ionisation is a standard procedure to ionise gaseous or vaporisable substances in organic mass spectrometry. In this work, a "softer" ionisation is introduced which seems to be an alternative ion source for reducing collision between substance molecules and the hot internal walls of the box. Through collision mainly found in impact ionisation sources, fragments are built especially from thermally sensitive substances falsifying the spectra. We present here photoelectron emitting materials for the soft ionisation using semiconducting compounds, galliumn nitride (GaN), and a representative of the borides, lanthanum hexaboride (LaB 6 ). They are evaluated by photoelectron spectroscopic …