The group’s current research projects include but not limited to the areas of micro, nano, and bio technology development; robotics, control systems, and sensors.

Electrical Properties of Chicken Herpes Virus Based on Impedance Analysis using Atomic Force Microscopy–Zhuxin Dong and Brock Schulte have been working with the chicken herpes virus. They have been studying the electrical properties of the virus to better understand the means to detect it within an organism. To help them they have been working with an impedance analysis system using atomic force microscopy (AFM).

Design, Fabrication and Measurement of CNT Based ISFET for NANO Devices–This research project dealt with carbon nanotubes due to their excellent electrical and mechanical properties, as well as their small size. These devices can be used for pH control and an AFM can test the conductivity of the carbon nanotubes with a conductive cantilever-tip structure.

Dielectrophoresis (DEP) Based Microfluidic Particle Separator–In this report Zhuxin Dong introduces a microfluidic system for manipulation and separation of micron-sized particles based on the combined use of negative dielectrophoresis (DEP) and hydrodynamic forces.

An Optical-Tracking Calibration Method for MEMS-Based Digital Writing Instrument–A Ubiquitous Digital Writing Instrument (UDWI) has been developed by our group to capture and record human handwriting or drawing motions in real-time based on a MEMS Inertial Measurement Unit (µIMU).

Result Images

Figure 1 shows a 3-D image of a 2х2 µm square from AFM scanning. In this image, there is a cavity in the middle, which is formed by thermal chemical vapor deposition of tetraethlyorthosilicate (TEOS). The diameter of the cavity is about 500 nm and the depth is about 9.8 nm. Besides a cavity, there are four carbon nanofibers surrounding the cavity and the spacing of each fiber is 1µm. For a fiber, the diameter is about 180 nm and the height is 8.0 nm.

Figure 2 is a 2-D image of a 2х2 µm square from AFM scanning. The vertical bar shows the height distribution: The darker, the deeper. Thus, it is obvious that there are two dark areas, which we regard as cavities. In addition, there are a few bright points surrounding the cavities; they are the carbon nanofiber tips.

Figure 3 is an image of the camera view. The camera is located on the top of the microscope. This camera view can be open in the control software for examining the location of the laser and observing the sample. In this image, the laser is placed right on the AFM probe tip. Under the probe, there are six arrays visible. On each array, there are carbon nanofibers as nanoelectrodes, which are the targets we are going to scan and measure.

Figure 4 is an image which shows how we measure the diameter and depth of a single cavity. The horizontal axis stands for the length of a line we draw on the scanned image across a cavity. And this image shows the cross section according to the line. Then we can measure any distance between two cursors, which can be located anywhere along the blue cross section curve.

Figure 5 shows the coordinate frames inside a digital pen integrated with 3-dimensional accelerometer, 3-dimensinonal gyroscope and 3-dimensional magnetometer. In order to sense efficiently, the accelerometer is very close to the pentip. The gyroscope is fabricated in the middle and the magnetometer located on the top. Based on this structure, the pen can sense enough information to reconstruct the character written by itself on any 3-dimensional surface. Eventually, it is possible to implement this system into an application for interfacing PC and other mobile computing devices.