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We present the design, fabrication and measurement results of a comb-driven electrostatic scanning micromirror. Instead of a conventional micromirror having uniform thickness across the entire reflective surface, a diaphragm mirror plate supported by an array of diamond-shaped frame structures is fabricated monolithically. The fabrication process is a simple sequence of silicon deep etch processes on both sides of the silicon-on-insulator (SOI) substrate without the substrate bonding process. The micromirror is fabricated on the device layer of the substrate. The mirror plate undergoes a rotational motion by an electrostatic force between the movable comb electrodes connected to the micromirror and stationary comb electrode formed on the handle wafer. A scanning micromirror with a 10 µm thick diaphragm mirror plate, having a planar dimension of 1.5 × 1.5 mm 2 , supported by an array of 110 µm thick rhombic support frames, was fabricated and tested. A mechanical deflection angle of 8.5 • at a resonance frequency of 19.55 kHz and a pressure of 7 mTorr was obtained. A prototype of the raster scanning laser projection display system was developed using the fabricated micromirror as the horizontal scanner and a galvanomirror as the vertical scanner, respectively.

Robust, processable, and bright quantum dot/organosilicate (QD/OS) hybrid films with uniform QD distribution are successfully demonstrated by grafting thiol-containing polymeric organosilicate (OS) ligands to the surface of QDs. It is found that the surface modified QDs show almost the same optical properties (i.e., in terms of emission PL spectra and quantum yields (QYs)) as those of pristine QDs initially covered with oleic acids. The QD/OS hybrid films based on the surface modified QDs show the uniform distribution of QDs within the films with all the beneficial properties such as high QY, improved environmental resistance against hydrochloric acid, and excellent optical transparency in the visible range. In addition, red, green, blue, and white QD/OS hybrid films with high color purity and a downconversion film, based on a mixture of red and green QDs, placed on top of a blue LED chip showing white emission were also successfully demonstrated with the QD/OS hybrids. We further demonstrate that cylinder-patterned QD/OS hybrid films are possible simply by applying unconventional imprint lithography. The QD/OS hybrid films with uniform distribution of QDs within the films could thus be applied as practical platforms, which have easy processability, high QY, and environmental stability, for optical devices based on functional nanocrystals.