Ultrahigh-vacuum apparatus for surface spectroscopy and characterization at cryogenic temperatures

Journal Article · Thu Jun 01 00:00:00 EDT 1989 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1140278· OSTI ID:6176902

Chia, V K.F.; Veirs, D K; Rosenblatt, G M

An ultrahigh-vacuum apparatus is described that enables the study of molecular adsorbates on well-defined single crystals at controlled temperatures from 14 to 900 K. Sample cooling is achieved with a closed-cycle helium refrigerator coupled to the sample holder via a flexible copper cable. This configuration maintains a 3-K temperature differential from the 11-K cryocold head to the sample and damps vibrations from the cyrocold head. The cyrogenic sample manipulator allows X, Y, Z translations, tilt, and rotation of an arm holding the sample through an arc of 270/sup 0/ about the vertical central axis of the vacuum chamber. The sample, mounted 12.7 cm from the central axis, may also be rotated 90/sup 0/ about a vertical axis through the sample. Rotation of the sample about a working circle radius of 12.7 cm allows the sample to be accessed for surface cleaning, characterization, and study by instrumentation whose physical size does not allow access by sample rotation about the chamber central axis alone. In our application, unenhanced surface Raman spectroscopy, low-energy electron diffraction, and Auger spectroscopy are carried out while maintaining a controlled sample temperature. Laser entry ports at two incident angles permit the sutdy of substrates with differing optical properties. Unenhanced surface Raman spectra of nitrogen physisorbed on a silver (111) surface are presented.

• Research Organization: Lawrence Berkeley Laboratory, Materials and Chemical Sciences Division, Berkeley, California 94720
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6176902
• Journal Information: Rev. Sci. Instrum.; (United States), Vol. 60:6
• Country of Publication: United States
• Language: English

Related Subjects

47 OTHER INSTRUMENTATION
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
SAMPLE HOLDERS
DESIGN
VACUUM SYSTEMS
ADSORPTION
AUGER ELECTRON SPECTROSCOPY
CRYOGENICS
ELECTRON DIFFRACTION
RAMAN SPECTROSCOPY
ULTRAHIGH VACUUM
ULTRALOW TEMPERATURE
COHERENT SCATTERING
DIFFRACTION
ELECTRON SPECTROSCOPY
LASER SPECTROSCOPY
SCATTERING
SORPTION
SPECTROSCOPY
440300* - Miscellaneous Instruments- (-1989)
420201 - Engineering- Cryogenic Equipment & Devices