| 1. |
|
|
| 2. |
- Bogdanov, A. L., et al.
(författare)
-
Fabrication of arrays of nanometer size test structures for scanning probe microscope tips characterization
- 1994
-
Ingår i: Journal of Vacuum Science & Technology B: Microelectronics Processing and Phenomena. - : American Vacuum Society. - 0734-211X. ; 12:6, s. 3681-3684
-
Konferensbidrag (refereegranskat)abstract
- A problem in scanning probe microscopy (SPM) is the unknown shape of the probing tip. Generally, the image is a convolution between the shape of the tip and the surface. Information of the shape of the probe may be gained by imaging very sharp tips. Here we present a method for making two-dimensional arrays of very sharp tips. The tip arrays were made of silicon using electron beam lithography with subsequent ion-beam etching. To achieve the best possible resolution, ultrasonic excitation was used during development of the bilayered PMMA resist. Thus, openings in the resist with size nearly equal to the spot size of the writing e-beam have been obtained. A further decrease of the radius of the tips was obtained by the choice of appropriate thickness for the masking NiCr layer. The tips were conical with a height up to 100 nm with a radius of the tip down to 10 nm. The tips were suitable for study of the shape of AFM probe tips, under condition that the tip array samples were rinsed in water prior to the measurement. Without the rinsing procedure, strong sticking forces between the probe and the sample would have eroded both of them. The regularity of the array provided an easy way to calibrate the lateral motion of the scanner
|
|
| 3. |
- Gershenson, M. E., et al.
(författare)
-
Quantum interference effects in percolated metal networks
- 1994
-
Ingår i: Physica B: Condensed Matter. - : Elsevier BV. - 0921-4526. ; , s. 1109-1110
-
Konferensbidrag (refereegranskat)abstract
- Quantum corrections (QC) to the resistivity due to weak localization (WL) and electron-electron interaction (EEI) have been measured for percolated metal networks with percolation coherence length z comparable to the quantum length scales-the phase-breaking length L and the thermal diffusion length LT. Far from the percolation metal-insulator transition (MIT) the `macroscopic' disorder is averaged over the quantum lengths (L,LTz) and the QC are of the universal two-dimensional (2D) type with R=R(z), where R(z) is the resistance per square at scales larger than z. A crossover 2D1D in the dimensionality of the QC and the Nyquist phase-braking mechanism is observed near the MIT, where zL,LT
|
|
