Synthesis of porous Si microparticles, AKA "Smart Dust" (7 Mb)
APPLE QUICKTIME movie showing synthesis of porous Si particles, including etch, liftoff, ultrasonic fracture, and transfer into syringe. Movie finishes with a series of scanning electron microscope images that zoom into the 30-nm pores of a porous Si microparticle (courtesy Jennifer Andrew). Filmed by Luo Gu, with help from the other lab members.
Lab shots of nanoworms, magnetic porous Si particles (36 Mb)
MPEG-4 movie showing various lab members synthesizing and characterizing some of the nanomaterials we work with in our lab. Movie finishes with a close-up of Ji-Ho Park with a syringe filled with his tumor-targeting nanoworms. Filmed by Luo Gu, with a lot of help from the other lab members.
Smart Dust self-assembling on a drop of oil (11 Mb)
Quicktime movie showing smart dust in a small flask. A drop of an oily pollutant (methylene chloride) is added and the clip then zooms in on a microscope image of the smart dust assembling itself at the oil/water interface. Each of the individual smart dust particles shown is about the size of the diameter of a human hair (50-100 microns).You can also download a high resolution version of this movie (23 Mb). Filmed by Jamie R. Link.
Chemical sensor made from a porous Si photonic crystal connected to a cell phone (12 Mb)
MPEG-4 movie showing a photonic crystal sensor that has been integrated with electronics (Ardueno board) that is then connected to a cell phone. Exposure to chemical vapor trips the sensor, and this information is then transmitted to a remote receiver via a commercial cell phone network. System constructed and filmed by Brian H. King.
Photoetch of n-type Si to make porous Si (2.7 Mb)
Quicktime movie showing the photoelectrochemical preparation of a porous Si sample by Prof. Jun Gao. CAUTION: HF is highly toxic and can cause severe burns on contact with the skin or eyes. Note for safety reasons we no longer recommend dispensing HF-containing electrolytes from spout bottles.
Smart dust in water (7.4 Mb)
A Quicktime movie showing microscopic "smart dust" particles dispersed in water. The Smart Dust is microscopic particles of porous Si optical rugate filters, removed from the Si substrate and ultrasonically fractured to break them up into particles. These photonic crystals change color depending on the chemicals in the pores. Experiment by T.J. Keilty and Michael Z. Szopiak.
Smart dust autonomously seeking ground (3 Mb)
A Quicktime movie showing microscopic "smart dust" particles dispersed in hexane, attracted by electrostatic forces to the finger of their maker. The Smart Dust is microscopic particles of porous silicon. Particles were given a static charge prior to the pictured experiment using a piezoelectric anti-static transducer. Experiment by Jason Dorvee.
Robot using a porous Si photonic crystal sensor (18 Mb)
A Quicktime movie showing a robot employing a modified line-tracker circuit that uses two porous Si photonic crystal sensors. The clip shows the robot being activated by and tracking a trail of liquid ethanol. It then shows the robot being exposed to water vapor and then ethanol vapor. It only responds to the ethanol vapor and ignores the water vapor. Made by Jason Dorvee.
Although the scope of our work at the University is limited to basic research into the fundamental properties of materials, many of the concepts developed in our labs have been translated to products and processes in the commercial world. Any commercial products and processes that emerge from our fundamental discoveries are outside the course and scope of our University-related employment; however, we actively encourage transition of technologies to the commercial sector with the assistance of UCSD’s Office of Innovation and Commercialization