Tetsuo Soga

Effect of sol processing parameters on dye-sensitized TiO/sub 2/ solar cell by spin-coating method

The sol-gel spin coating method has been explored to prepare TiO/sub 2/ thin films for dye-sensitized TiO/sub 2/ solar cell application. Sol concentrated at 40/spl deg/C with 40% polyethylene glycol (PEG) by weight of TiO/sub 2/ added to the sol is found to give smooth, crack free and highly porous film with high cell efficiency. Thickness dependent optical absorption and cell performance are studied. Though light absorption gradually increases with film thickness, a saturation in short-circuit current occurs at higher thicknesses. Efforts are also made to improve the cell performance by modifying the electrolyte solvent and adding 4-tert butylpyridine.

ALGAAS/GAAS TJS laser diodes fabricated on Si substrates by MOCVD

Abstract AlGaAs/GaAs TJS (Transverse Junction Stripe) laser diodes are fabricated on p-Si substrates by MOCVD. The preferential Zn diffusion is performed in DH structure on Si at 650°C using sputtered SiO 2 as diffusion mask. The diodes have lased at room temperature (27°C) pulsed conditions with the minimum threshold current of 379mA.