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Techniques to reduce random noise in complementary metal oxide semiconductor (CMOS) image sensor chips with pixel sizes as small as 2.2 ×2.2 µm2 are addressed. By applying dummy heat annealing and plasma nitrided (PN) oxide, random noise can be reduced by more than 40%. Measured results indicate that the gate oxide–Si interface is improved by a dummy heat treatment, and PN oxide is a good choice as a gate oxide for image sensors, since it has an optimal nitrogen profile as a gate oxide while it effectively suppresses boron penetration. The results show the importance of nitrogen profile control in gate oxides and of oxide curing for low noise characteristics in CMOS image sensors.

A novel tandem iodocyclization has been achieved by the regioselective ring-opening of epoxide and by the following intramolecular 1,4-cycloaddition of α,β-unsaturated ester with catalytic amount of SmI 2 and I 2 (1.2-2.5equivalent) under mild and neutral reaction conditions.

Various epoxy esters readily reacted with SmI 2 (2 equiv) in the presence of ethyl bromoacetate (1 equiv) and HMPA (6 equiv) under mild conditions (THF, −78 °C, 2 h, Ar) providing the corresponding γ-lactones via tandem epoxide opening-cyclization reaction in good to excellent yields.

We demonstrate a new postmetallization annealing and ultraviolet (UV) treatment process for reducing the dark current of image sensors. The new method utilizes a large amount of hydrogen in a plasma-silicon nitride film (p-SiNx) as a hydrogen diffusion source. Through charge pumping measurement, it is proved that this method effectively reduces the interface trap density of pixel transistors, thereby decreasing the dark current of image sensors. Although the postetch process for removing p-SiNx films induces plasma damage during the etch step, the damage can be effectively cured by the subsequent UV annealing.

Regio- and stereoselective iodinative cleavage of 2′,3′-anhydropurine nucleosides was achieved with samarium diiodide and ethyl bromoacetate to produce the corresponding 3′-iodopurine nucleosides, which were then converted to 3′-deoxypurine nucleosides including the natural product cordycepin.

A new SmI2-promoted intramolecular reductive cyclization of β-(α-bromo siloxy) carbonyl compounds is reported.

Various epoxy esters readily reacted with SmI 2 (2 equiv) in the presence of ethyl bromoacetate (1 equiv) and HMPA (6 equiv) under mild conditions (THF, −78 °C, 2 h, Ar) providing the corresponding γ-lactones via tandem epoxide opening-cyclization reaction in good to excellent yields.

A novel tandem iodocyclization has been achieved by the regioselective ring-opening of epoxide and by the following intramolecular 1,4-cycloaddition of α,β-unsaturated ester with catalytic amount of SmI 2 and I 2 (1.2-2.5equivalent) under mild and neutral reaction conditions.

A new SmI2-promoted intramolecular reductive cyclization of β-(α-bromo siloxy) carbonyl compounds is reported.