Scanning probe and its preparation method

Abstract

The invention provides a scanning probe and a preparation method thereof. The scanning probe includes: a substrate, including a flat plate portion and a needle-shaped protrusion extending from one end of the flat plate; an electrostatic probe, disposed on the protrusion; a single-electron transistor, disposed on the flat part and opposite to the electrostatic probe. The preparation method includes: forming an electrostatic probe and a single electron transistor; forming a second sub-slab portion and a needle-shaped second sub-protrusion portion; forming a first sub-slab portion and a needle-shaped first sub-protrusion portion, and The edge of the first sub-protrusion portion exceeds the edge of the second sub-protrusion portion, and the edge of the first sub-flat portion exceeds the edge of the second sub-flat portion. The scanning probe provided by the invention has small lateral etching and good appearance, can realize high-speed, high-sensitivity, and high-resolution charge detection, and has a simple preparation method and high yield.

Description

technical field [0001] The invention belongs to nanometer devices and nanometer processing technologies, and in particular relates to a scanning probe and a preparation method thereof. Background technique [0002] Single-electron transistors are based on the Coulomb blocking effect and single-electron tunneling effect, which can detect small charge changes at the micro-nano scale and within its vicinity with high sensitivity. The core structure of a single-electron transistor is a quantum dot or Coulomb island that is only a few to tens of nanometers in size and is very sensitive to charges. Regulation of Coulomb Island. Single-electron transistor charge sensitivity can reach 10 -6 e / Hz 0.5 , but the bandwidth is relatively small, generally less than 1MHz. Integrating an extremely charge-sensitive single-electron transistor on the tip of the probe can simultaneously realize charge scanning detection and topography imaging. At present, there have been relevant research ...

AI Technical Summary

Problems solved by technology

At present, there have been relevant research reports on the single electron transistor scanning probe (SET Scanning Probe) in the world, and the radio frequency single electron transistor (Radio Frequency-SET) technology has also been realized, but the radio frequency single electron transistor with two functions integrated Scanning probes have not yet been implemented and applied

[0003] The existing process for preparing single-electron transistor scanning probes includes: 1. Al / Al is prepared by multi-angle evaporation and oxidation of Al on the tip of the fiber optic probe. 2 o 3 The single-electron transistor probe (SET Scanning Probe) has successfully realized the charge detection and geometric morphology imaging of the sample surface by the single-electron transistor probe. However, this preparation method has a complicated process, low yield, and cannot be used in large quantities Preparation; 2. In order to prepare replaceable single-electron transistor scanning probes in large quantities, the mature MEMS process can be used to prepare Al / Al by repeatedly depositing Al on the silicon substrate and oxidizing it. 2 o 3 The single-electron transistor scanning probe, the single-electron transistor on the probe has a good Coulomb blocking effect, and realizes the scanning imaging function of the geometric shape of the probe, but the process of preparation is relatively complicated, and based on Al / Al 2 o 3 Type single-electron transistors, the operating temperature is usually below 300mK, and cannot work at higher temperatures

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