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The use of highly corrosive chemicals to remove nano-particles on the surface of the wafer, results in substrate losses. This has resulted in the use of megasonics which provides acoustic cavitation to remove small particles. The megasonic wave does generate bubble cavitation which applies mechanical force to wafer structure, the violent cavitation such as transit cavitation or micro jet will damage the patterned structures [1,2]. A new megasonic technology is proposed in this paper, this technology provides stable control of bubble cavitation, without pattern damage at the different modes. The technology shows better particle performance when compared with the industry standard two-fluid nozzle cleaning technology. This Timely Energized Bubble Oscillation mode provides stable cavitation with a wide power window. It is unlike conventional megasonic which creates transit cavitation and damage when the bubble implodes. This new megasonic technology can be used to clean “sensitive” structures at 28nm and below without any pattern damage.

In order to explore a smart carrier which can control drug delivery in special pH environment, a type of nanometer material, namely, poly acrylic acid acrylamide (P(AA-AM)) was synthesized with acrylic acid and acrylamide as monomers. Its structure was determined using Fourier transform infrared spectroscopy (FTIR) and its swelling properties were tested by measuring its weight evolution. The drug delivery control potential was estimated by monitoring its swelling performances in the solutions of different pH values. The cycle characteristics were also investigated to determine its degradation properties in the environment. The results indicate that the synthesized material is sensitive to pH and is suitable for controlling drug delivery at the pH range from 10 to11 and below 7. Furthermore, this material can be automatic decomposition in the environment so that it is a degradable green material without causing burden to the environment.