No abstract

In this study, a self-assembled monolayer (SAM) of methoxy-poly (ethylene-glycol)-silane (mPEG-sil) was used to modify the silicon dioxide surface of polysilicon nanodevices (PNDs) to act as a passivation layer that inhibits nonspecific binding of proteins and reduces localized Joule heating power. Selective modifications of 3-aminopropyltrimethoxysilane (APTMS), NHS-biotin and dye-labeled Streptavidin on the removal regions were characterized. These PNDs, which consist of a two-level doping profile, were designed to confine heat in the low-level doping region during localized Joule heating. Localized Joule heating with pulse bias was examined in both vacuum and ambient, which indicated the removal region was longer in vacuum for the same pulse bias. Moreover, a comparison of selectively and nonselectively modified PNDs observed in time-lapsed fluorescence detection of dye-labeled Streptavidin showed a higher increasing rate in fluorescence intensity (∼2× enhancement) in the selectively modified PNDs. Finally, a COMSOL simulation was employed to evaluate the temperature distribution in the PNDs, with results showing that heat confinement was observed in the low-level doping region and a temperature very close to 673 K was achieved while applying a pulse voltage (40 V, 5 μs) to remove mPEG-sil.

Variations of the voltage response between source and drain electrodes of an AlGaN/GaN high electron mobility transistor by the green laser light or ultraviolet (UV) illumination are studied. A subsequent green laser illumination causes the voltage between the electrodes to increase with background UV illumination. Interactions between surface states and excess carriers generated by the UV light are proposed to be responsible for the voltage increase. Excess electrons are captured by the positively charged surface states after injection into the surface region with the assistance of the green laser light and result in a reduced two-dimensional electron gas density.

In this paper, a method for determining the approximated minimum-bounding box is presented. This method can only be used in the model that has finite vertices. A concept of the minimum span is introduced to determine one length of the bounding box according to a flush edge. After calculating a minimum span, the minimum-area rectangle of the projection is required to be one candidate of minimum-bounding boxes. In many applications, the volume of the bounding box is requested as small as possible. This paper provides an additional property to keep both one length and one rectangle of the bounding box are as small as possible.