SELF-ALIGNING SCANNING PROBES FOR A SCANNING PROBE MICROSCOPE

Abstract

Scanning probes are provided for alternative use in a scanning probe microscope. The scanning probes have micro cantilever beams of different lengths whose one end has a scanning tip for scanning a sample and whose other end has a holding element for the non-permanent attachment of the scanning probe to a support element secured in position on a probe holder, and where corresponding alignment elements are incorporated in the holding element and in the support element that align the holding element in automatically reproducible fashion relative to the probe holder when coupled with the support element. The distance between the scanning tip and a defined reference point of the holding element is constant in each case so that an alignment of the scanning probe in longitudinal direction is not necessary when the scanning probe is exchanged.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Below, the invention is explained in detail with reference to an embodiment shown in the drawings. Here, the figures of the drawings and their description reveal additional characteristics and advantages of the invention.

A mechanism is shown that permits a highly precise self-alignment of scanning probes with micro cantilever beams of different lengths for scanning probe microscopy during the exchange of the scanning probes. The mechanism includes two interacting components, the support element that is firmly connected with the scanning head of the scanning probe microscope, and specially adapted scanning probes. Specifically,

FIG. 1 shows a view of a scanning probe coupled to a support element;

FIG. 2 shows a view of the support element and the scanning probe from FIG. 1 in non-coupled condition; and

FIG. 3 shows a comparison of coupled scanning probes in accordance with FIG. 1 with micro cantilever beams of different lengths.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a scanning probe 1 in accordance with the invention whose holding element 2 is coupled with a support element 3 of a probe holder (not shown). Arranged behind the holding element 2, it has a micro cantilever beam 4 at whose one end 5 a scanning tip 6 rises perpendicular to the micro cantilever beam 4, as shown in FIG. 1a. This scanning tip 6 serves to scan a sample (not shown). The support element 3 is secured in position on the probe holder, and the scanning probe 1 is connected non-permanently to the support element 3 via the holding element 2. The support element 3 and the holding element 2 are essentially square and have recesses and raised sections serving as alignment elements 8, 8′, 8″, 16, 16′, 16″, 18, as shown in FIG. 2a to 2d, through which the support element 3 and the holding element 2 act on each other by means of positive contact.

FIGS. 2 a, 2 b show the scanning probe 1 without the support element 3. On the contact side 7 associated with the support element 3, the holding element 2 has alignment elements 8, 8′, 8″ in the form of recesses with an elongated prismatic shape. Angled surfaces 10, 10′ of the alignment elements 8, 8′, 8″ and inclined lateral surfaces 11, 11′ of the holding element 2 serve as contact surfaces for the support element 3 and cause the automatic alignment of the holding element 2, and therefore of the entire scanning probe 1, when the holding element 2 is coupled with the support element 3.

The scanning tip 6 provided at the end 5 of the micro cantilever beam 4 has a constant distance 12 from a predetermined reference point 9 of the holding element 2, that is independent of the length 14 of the micro cantilever beam 4 in each case for all scanning probes shown, as can be seen from FIG. 3.

FIGS. 2 c, 2 d show the support element 3 in non-coupled condition. From its flat surface 15 associated with the contact surface 7 of the holding element 2, alignment elements 16, 16′, 16″ protrude that act on the alignment elements 8, 8′, 8″ and precisely position the scanning probe 1 when the scanning probe 1 is coupled with the support element 3. For pre-alignment purposes, angled surfaces 17, 17′ of an attachment guide 18 serve in conjunction with the inclined lateral surfaces 11, 11′ of the holding element 2.

The alignment elements 8, 8′, 8″ of the holding element 2 are located centrally relative to a reference point 9 of the holding element 2, and the alignment elements 16, 16′, 16″ of the support element 3 are located centrally relative to a reference point 19 of the support element 3. They show the same distance and the same location relative to their respective reference points 9 and 19. In the coupled condition of the scanning probe 1, the reference point 9 and the reference point 19 face each other so that the alignment elements 8, 8′, 8″ of the holding element 2 and the alignment elements 16, 16′, 16″ of the support element 3 are in alignment with each other. The alignment elements 8, 8′, 8″ and 16, 16′, 16″ are essentially of complementary design, with the alignment elements 8, 8′, 8″ of the holding element 2 having a different length than the alignment elements 16, 16′, 16″ of the support element 3. They engage each other with positive contact, as shown in FIGS. 1a, 1b.

FIG. 3 shows three scanning probes 1 as proposed by the invention with micro cantilever beams 4 of different lengths 14, shown as examples in FIGS. 3a, 3b, and 3c. Here, the scanning tip 6 located at the end 5 of each micro cantilever beam 4 has an identical distance 12 from each reference point 9. The total length 20 of the scanning probe 1 that is determined by the front end 5 of the micro cantilever beam 4 and the rear edge 21 of the holding element 2 is constant in all three examples. The different length 14 of the micro cantilever beam 4 in each case is achieved by the variation of a length 22 of the holding element 2, which has the effect that the front edge 23 of the holding element 2 that follows the rear end 13 of the micro cantilever beam 4 has a different position relative to the reference point 9 of the holding element 2 in each case.

Although the invention has been shown and described with respect to certain preferred embodiments, it is obvious that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications, and is limited only by the scope of the following claims.

Claims

1. A combination of scanning probes for alternative use in a scanning probe microscope where the scanning probes have a micro cantilever beam whose one end has a scanning tip for scanning a sample and whose other end has a holding element for the non-permanent attachment of the scanning probe to a support element secured to a probe holder, and where corresponding alignment elements are incorporated in the holding element and in the support element that align the holding element in automatically reproducible fashion relative to the probe holder when coupled with the support element, wherein the micro cantilever beams of the scanning probes have different lengths and in each scanning probe the distance between the scanning tip and a defined reference point of the holding element is constant.

2. The combination of scanning probes according to claim 1, wherein with each of the scanning probes, the distance between the defined reference point of the holding element and a front edge of the holding element that is associated with the micro cantilever beam may vary, depending on the length of the micro cantilever beam.

3. The combination of scanning probes according to claim 1, wherein the scanning probes have the same length from the scanning tip to a rear edge of the holding element that faces away from the micro cantilever beam.

4. The combination of scanning probes according to claim 2, wherein the scanning probes have the same length from the scanning tip to a rear edge of the holding element that faces away from the micro cantilever beam.

5. The combination of scanning probes according to claim 1, wherein the corresponding alignment elements interact in complementary physical arrangement.

6. The combination of scanning probes according to claim 5, wherein the corresponding elements comprise raised alignment elements and recessed alignment elements for receiving the raised alignment elements.

7. The combination of scanning probes according to claim 1, wherein the corresponding alignment elements provide alignment in all three spatial directions.

8. A process for manufacturing scanning probes for a scanning probe microscope where the scanning probes have micro cantilever beams of different lengths whose one end has a scanning tip for scanning a sample and whose other end has a holding element for the non-permanent attachment of the scanning probes to a support element secured in position on a probe holder, and where corresponding alignment elements are incorporated in the holding element and in the support element that align the holding element in automatically reproducible fashion relative to the probe holder when coupled with the support element, where the scanning tip of the scanning probe is precisely positioned relative to the probe holder, including the steps of: (a) designing and manufacturing a commonly usable support element with alignment elements for the precision alignment of scanning probes with micro cantilever beams of different lengths;(b) designing the rear part of the holding element opposite the support element while incorporating alignment elements that correspond with the alignment elements of the support element;(c) determining a defined reference point in an area around the alignment elements of the holding element, at a certain constant distance from which the scanning tip is to be arranged when the length of the micro cantilever beam varies;(d) designing the front part of the holding element associated with the micro cantilever beam, with variation of the distance of the front edge facing the scanning tip and the reference point of the holding element until the desired length of the micro cantilever beam is obtained;(e) designing the micro cantilever beam with the scanning tip at its end, with the scanning tip arranged at a certain distance from the reference point of the holding element; and(f) manufacturing the scanning probe.