A complementary metal-oxide-semiconductor compatible monocantilever 12-point probe for conductivity measurements on the nanoscale

Abstract

A complementary metal-oxide-semiconductor compatible monocantilever 12-point probe for conductivity measurements on the nanoscale. Applied Physics Letters, 93(9), 093104.

The conductivity of Bi(111) investigated with nanoscale four point probes

“…Further details of the probes with the ultrahigh vacuum instrument and measurement procedure can be found elsewhere. 20,23,24 In order to vary the contact spacing, two different techniques are employed. First, since each monocantilever probe has 12 contacts and since only 4 are required to perform the conductivity measurement, the contact spacing can be changed by simply selecting different contacts.…”

“…In the present paper, we address this problem by probing the conductance of Bi͑111͒ using a newly developed nanoscale four point probe. 20 Four point probes have successfully been used to determine the surface conductance of semiconductor surfaces for cases where the conductance of the space charge layer and the bulk are negligible compared to that of the surface. [21][22][23][24] If the goal of the experiment is to determine the conductance due to the surface states of Bi, the best approach for doing this is to use a Bi single crystal as a sample, not a thin film with concomitant problems of quantum size effects and carriers induced at the film-substrate interface.…”

“…We therefore performed our measurements on the ͑111͒ surface of Bi for which the electronic structure and even the lifetime of the surface states are well known. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] growth direction for thin films. Our findings have direct relevance for the study of the semimetal to semiconductor transitions in these films.…”

Surface-Dominated Transport on a Bulk Topological Insulator

“…In the present work, the direct measurement of surface transport is achieved by combining high-quality bulk-insulating crystals of Bi 2 Te 2 Se with four-point transport measurements on the clean surface in ultrahigh vacuum and on a variable length scale. The transport measurements shown in Figure (a) were performed using the same piece of Bi 2 Te 2 Se on two instruments: a four tip scanning tunnelling microscope (4STM) − and a collinear 12-point probe (12pp). , These are shown in Figure b,c. For the 4STM, the scanning electron microscopy image is that of the four contacts placed on the actual surface of Bi 2 Te 2 Se.…”

Evaluation of four-point transient potential drop on conductive plates

“…Although we are mainly motivated by measurements on macroscopic specimens and structures, the technique also finds applications in semiconductor characterization using special probes of sizes approaching the nanoscale. 4 Alternating current potential drop (ACPD) measurements are commonly made at frequencies where the electromagnetic skin depth is small, meaning that the current flows in a near-surface layer which results in high sensitivity to surface-breaking cracks. For this reason, ACPD is often used as an alternative to the traditional direct current potential drop (DCPD) method.…”