| AVS 54th International Symposium | |
| Nanometer-scale Science and Technology | Tuesday Sessions |
| Session NS-TuP |
| Session: | Nanometer-scale Science and Technology Poster Session I |
| Presenter: | Y.J. Song, National Institute of Standards and Technology |
| Authors: | Y.J. Song, National Institute of Standards and Technology S.R. Blankenship, National Institute of Standards and Technology J.N. Crain, National Institute of Standards and Technology J.A. Stroscio, National Institute of Standards and Technology |
| Correspondent: | Click to Email |
We describe the design and construction of an ultra-low-temperature (20 mK), high magnetic field (15 T) scanning tunneling microscope (ULT STM) system. This ULT STM consists of an ultra-high-vacuum-compatible dilution refrigerator (DR) and associated UHV systems. The DR was designed and constructed to allow two independent modes of 3He condensation: a traditional 1K pot condenser, or a Joule-Thomson condenser for possible lower noise operation. The system includes extensive vibration isolations and RF shielding. We describe the cooling power characteristics and temperature measurement system of this versatile DR, which reaches a base temperature of 10 mK without STM running. For STM/STS measurements a custom-designed STM module suitable for operation at mK temperatures is described. The STM body is made from coin silver which is rigid and thermally conductive in the mK regime. The whole STM module can be transferred from the upper, room-temperature chamber where the sample and tip can be easily exchanged. The sample holder has five isolated electrical contacts which are also used for kinematic mounting of the sample. This allows 4-probe electrical measurements to be performed simultaneously with STM measurements for microscopic transport studies. This STM module has ± 2 mm of x and y travel and in-situ deposition capabilities on the STM sample mount. Current progress and research plans will be discussed.
1 This work is supported in part by the Office of Naval Research and Korea Research Foundation.