In this paper we present the wafer-scale fabrication of molded AFM probes with high aspect ratio ultra-sharp three-plane silicon nitride tips. Using (111) silicon wafers a dedicated process is developed to fabricate molds in the silicon wafer that have a flat triangular bottom surface enclosed by three {111} side planes. By conformally coating the mold with a sufficient thick layer, the mold is sharpened, removing the flat bottom surface in the silicon mold, leaving a mold ending in three {111} side planes, which always intersect in a point. This ultimately results in AFM probes with tetrahedral tips consisting of three planes, thus the tips have ultra sharp apexes. We used silicon nitride to mold the probes in order to obtain more wear resistant probes compared with commonly used silicon. Inspection of the fabricated tips shows a tip radius of less than 4 nm.

We present the design, fabrication and characterization of an electrostatically actuated AFM probe. The probe consists of two cantilevers, a relatively long, stiff cantilever on which end a smaller and softer cantilever with a sharp tip is incorporated. The deflection of the small cantilever is controlled by an electrostatic gap-closing actuator, which is monolithically integrated on the cantilevers. A combination of a small and fast cantilever with an integrated electrostatic actuator allows for a high frequency operation and high speed AFM imaging. We have designed and fabricated a probe with the large cantilever having a stiffness of over 400 N/m and small cantilevers with a stiffness of up to 3.2 N/m and a resonance frequency up to 643 kHz. We have confirmed a proper operation of the probe using high-speed imaging (8 scan lines per second) in electrostatically driven tapping mode.

We present a process for batch fabrication of a novel scanning microscopy probe for thermal and magnetic imaging using standard micromachining and conventional optical contact lithography. The probe features an AFMtype cantilever with a sharp pyramidal tip composed of four freestanding silicon nitride nanowires coated by conductive material. The nanowires form an electrical cross junction at the apex of the tip, addressable through the electrodes integrated on the cantilever. The cross junction on the tip apex can be utilized to produce heat and detect local temperature changes or to serve as a miniaturized Hall magnetometer enabling, in principle, thermal and magnetic imaging by scanning the probe tip over a surface. We have successfully fabricated a first probe prototype with a nanowire tip composed of 140 nm thick and 11 µm long silicon nitride wires metallized by 6 nm titan and 30 nm gold layers. We have experimentally characterized electrical and thermal properties of the probe demonstrating its proper functioning.978-1-4244-5764-9/10/$26.00 ©2010 IEEE

The fabrication of sharp tips manufactured using silicon or using a silicon mold is a widely used method with a wide range of applications. In this study, we extend our work on the fabrication of tetrahedral molds in (111) silicon and the fabrication of tips based on those molds. We present multiple strategies to make a range of different structures out of silicon-rich nitride, focusing on an approach that takes advantage of oxidation sharpening to improve both the aspect ratio and the tip radius, as well as to make the fabrication process both more efficient and versatile. In this way, single tips and so-called tripod tips with a radius of less than 3 nm are successfully fabricated and used in an AFM probe to show the functionality of the tips.

In this paper, we present latest results of a thermopneumatic microactuator based on polymer membrane and silicon technology. This device has application in distributed air-jet planar micromanipulation to levitate and convey small objects by changing air-flow direction on the surface. Our technology, combining deformable polymer membrane and movable silicon nozzle fabrication, offers many advantages compared to classic silicon technology, e.g. pneumatic microactuator array device. Those advantages are as follows: low-cost, reliable, simple batch fabrication process, multi-directional (4 directions) air-jet flow, low driving voltage (≤ 5 V), durability under high airpressure, higher transparency for implementing photodetection capabilities, and enabling technology to use flexible and smart materials in MEMS.