| AVS 55th International Symposium & Exhibition | |
| Nanometer-scale Science and Technology | Wednesday Sessions |
| Session NS+NC-WeA |
| Session: | Nanoscale Devices and Sensors |
| Presenter: | D.F. Ogletree, Lawrence Berkeley National Laboratory |
| Authors: | D.F. Ogletree, Lawrence Berkeley National Laboratory Tzv. Ivanov, Technical University of Ilmenau, Germany Y. Sarov, Technical University of Ilmenau, Germany I.W. Rangelow, Technical University of Ilmenau, Germany |
| Correspondent: | Click to Email |
A scanning probe microscope has been integrated into a variable-pressure scanning electron microscope for in-situ nanoscale experiments. The heart of the instrument is a self-sensing, self-actuated cantilever1 oscillated at resonance for non-contact dynamic force or tapping mode imaging. We have employed piezoresistive readout and thermally driven bimorph actuation. The integrated Si tips have been formed at the end of the cantilever by a micro-machining process. A digitally-synthesized sine wave of variable frequency and amplitude excites the cantilever by driving an integrated resistor which generates thermal stress. Lever deflection is monitored by an integrated piezoresistive sensor, and the SEM is used to calibrate the sensor response. A commercial digital phase-lock loop controller2 adjusts the drive signal to maintain a constant oscillation amplitude and fixed phase shift relative to the drive frequency. A lab-built piezo scanner including a lateral translation system and a commercial nanotranslator for the tip approach complete the system. The system performance and noise levels will be compared for operation at the first, second and third resonant modes of the cantilever sensor, and the effects of ambient gas pressure will be discussed.
1Ivo W. Rangelow, Microelectronic Engineering 83 (2006) 1449–1455.
2PLLpro, RHK Technology, Inc., Troy, Michigan, USA.