arXiv subjects

H. Saragih

Publications and source records attributed to H. Saragih.

3 recordsLinked to original sources

arXiv2001

Application a-Si:H and Its Alloys for Photoreceptor Devices

Photoreceptor devices have been fabricated for positive corona with multi-layer structure of glass/ZnO /i-a-SiC:H /i-a-Si:H /p-a-SiC:H /Al type by using dual chamber plasma enhanced chemical vapor deposition (PECVD) system. 10% Silane (SiH4) and diborane (B2H6) gases diluted in hydrogen (H2) and 100% methane (CH4) gas were used as gas source. As the top passivation layer, the i-type a-SiC:H with optical band-gap of 2.93 eV was used. This highest optical band-gap was selected to allow more illumination through the photo-conductive layer. The i-type a-Si:H which has optical band-gap of 1.78 eV was used as the photo-conductive layer. The conductivity of p-type a-SiC:H films was also measured. The p-type a-SiC:H film with the lowest dark conductivity was then used as the bottom blocking layer to prevent charge injection from photo-conductive layer to the conductive electrode. The surface voltage characteristic of the device was also investigated. It decays as a function of time, with the maximum surface voltage applied is 120 volts.

cond-mat↗

arXiv2001

Spectral Response of Al/Si Photodiode as IR Sensor

Al/Si photodiode were prepared by successive of deposition of Aluminum thin films on p-type Si (100) using coprecipitation method by evaporator in vacuum 2.0E-4 torr. The measured signals are attributed to a spectral response, which appears in the studied photodiode. The photodiode Al/Si is sensitivity over a broad range of IR wavelengths from 800 to 1000 nm, when illuminated with discontinuous light at chopper frequency 200 Hz. The spectral response distribution that sensitivity peaks appear when the measurement was performed using the ac mode. The peak was at 981 nm, the incident radiation power (Pi) at the surface was 25 microwatt/cm2, the current signal (Ip) was 12.2 nA, the quantum efficiency was 6.16 % and the current sensitivity was 0.488 nA/microwatt/cm2.

cond-mat↗

arXiv2001

Preparation of Bi4ti3o12 Thin Films by a Pulsed Laser Ablation Deposition (PLAD) Method and their Applications for Ultraviole Detectors

Bi4Ti3O12 (BIT) has been considered as material for UV detector since it has optical band gap of about 3.5 eV. Unlike the most used material for this purpose, such as GaN and AlN, BIT is a ferroelectric oxide material. It has shown good detection properties in the UV regions. We have developed a Pulsed Laser Ablation Deposition (PLAD) method for preparation of BIT thin films. The BIT films were grown on Si/SiO2/Pt(111) substrates and these films exhibit good crystalline properties with preferential orientation in c-axis. A structure of Al/Bi4Ti3O12/Pt(111)/Si(100) was fabricated for measurement of spectral distribution of the voltage responsivity. The maximum voltage responsivity and the spectral distribution significantly depend on the films preparations and treatments.

cond-mat↗