The Penn State Research Foundation

Biotechnology Research and Development Corporation

Penn State Research Foundation and Biotechnology Research

The Penn State Research Foundation, Penn State Rsrch Foundtn &

Stephan J Stranick

Paul S Weiss

A system for transporting in a vacuum chamber sample holders and samples between a holder tray and a location for use with a surface analytical instrument is disclosed. Also provided is a system including a microwave coaxial cable connecting the tip terminal of a scanning tunneling microscope to a microwave signal source and a system for clamping a heater to a sample holder in order to heat the sample.

System for analyzing surfaces of samples

Multiple frequency sources are used to apply a time varying signal to a scanning tunneling microscope and a current or voltage passing between the electrodes of the microscope is measured by a microwave spectrum/network analyzer which detects simultaneously at the multiple input frequencies and combinations thereof. This permits multiple substances to be monitored simultaneously. By choosing appropriate frequencies of input signals to be mixed or combined before application to the sample, it is possible to measure at a difference frequency which may improve signal to noise ratio and possible to match generating and reaction potentials and relaxation times to render detection possible. When applied to an array of Coulomb blockade devices used as a current standard, accuracy of the standard can be tested and the signal-to-noise ratio can be improved in the measurements, or the thresholds of the devices can be detected. Multiple frequency sources of light are used to apply a light signal to a scanning near-field optical microscope. After being modulated by the sample, the signal is detected and a spectrometer which detects simultaneously at the multiple input frequencies and combinations thereof. This permits multiple substances to be monitored simultaneously.

Multiple source and detection frequencies in detecting threshold

By applying a voltage or signal and withdrawing or injecting an electron or electrons to a layer of material, it is possible to write, erase or read data electrochemically. The layer of material has at least one portion that will reversibly change between charge states in response to the applied voltage or signal and the withdrawal or injection of an electron or electrons. Alternatively, the material of the layer may be such that the portion of the layer of material will dissociate into components in response to the applied voltage or signal and injection or withdrawal of an electron or electrons. The stored data may be read using a scanning tunneling microscope by applying a voltage or signal thereto and detecting the current through, voltage across or signal reflected from the layer to detect the different charge states or structures of different portions of the layer. The signal or voltage applied can be a DC or AC signal, a signal pulse or transient or various combinations thereof. By using a material with more than two charge states or with multiple locations each with different charge states and by applying a signal with and detecting at a single or multiple frequencies, it is possible to write, erase or read multiple bits of information simultaneously.

Reading and writing stored information by means of electrochemistry

A microwave sweep oscillator is used to apply an AC signal from the probe tip of a scanning tunneling microscope to a sample, and the reflected signal from the sample is measured by a microwave spectrum/network analyzer, or another device capable of measuring amplitude versus frequency. The frequency of the signal applied by the oscillator may be swept across a spectrum and the optimum frequency of the spectrum is determined so that an improved image of the surface of a sample may be obtained. The spectrum of a known substance may also be recorded and used as a signature for identifying components of an unknown substance by comparison. When the amplitude of the AC signal applied is increased, a sudden change in the re

System for imaging and detecting threshold phenomena associated with

A microwave sweep oscillator is used to apply an AC signal cross a scanning tunneling microscope and the current or voltage passing between the electrodes is measured by a microwave spectrum/network analyze

Growing community of inventors

State College, PA, United States of America

Stephan J Stranick