Akishige Murakami

5.3: Novel Design for Color Electrochromic Display

developed a technology for a new full-color reflective electrochromic display (ECD) based on the subtractive color mixing model. This improves display brightness and color reproducibility. Additional advantage is simple production process. An active matrix driving of the full-color reflective ECD has been demonstrated successfully.

Properties of Silicon-Oxygen Alloy Films Prepared from SiH4+CO2 Gas Mixture

Measurement of electrical properties, etch rates in HF(49%) and HF-HNO 3 (49% HF:63% HNO 3 =1:20) solutions and X-ray photoemission spectra are reported for amorphous silicon-oxygen alloy films (a-SiO x :H) prepared by r. f. glow discharge decomposition of a SiH 4 -CO 2 gas mixture. Activated band conduction is observed in the temperature range of 324-424 K. Though the addition of oxygen causes a decrease in the conductivity, the activation energy for conduction remains at a constant value of around 1.0 eV in the films with oxygen content x from 0.17 to 0.5. The broadening toward the high binding of the Si-2p core level in X-ray photoemission spectra with oxygen content is explained by the effects of oxygen atoms incorporated into the films

Properties of Photosensor with Amorphous Si:H/SiOx:H Double-Layer Structure

A new amorphous silicon photosensor with glass/Cr/a-Si:H/a-SiOx:H/ITO structure was prepared. Initially, the photoresponse of this structure to a light pulse is about 750 times slower than that of the photosensor with the inverse (glass/ITO/a-SiOx:H/a-Si:H/Cr) structure. The X-ray photoemission spectra show that the a-SiOx:H surface is additionally oxidized during deposition of the ITO electrode. A fast response with a rise time of less than 1 ms can be obtained by treating the a-SiOx:H surface with boron plasma or depositing the boron-doped a-SiOx:H layer onto the undoped a-SiOx:H layer before the ITO deposition.

A New Type of Heterojunction a-Si Photodiode for Lensless Contact-Type Image Sensor

Using boron-doped and nondoped a-SiOx:H layers as photoreception windows, an ITO/a-SiOx(B):H/a-SiOx:H/a-Si:H/Cr heterojunction photodiode is constructed. The collection efficiency for photocarriers is improved over the wavelength range of visible light by this structure. The photo/dark current ratio of 5×103 is obtained at an applied voltage of -5 V. The photocurrent retains over 80% of its initial value over 2×104 seconds under the irradiation of AM1. With this photodiode, a lensless contact-type image sensor is realized with 8 bits/mm, A4 size and 2.5 ms/line.