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In this paper investigation photocurrent of MS Schottky photodiode by using transparent electrode. The transparent material use in this investigation is indium tin oxide (ITO). Transparent electrode can help to get more photocurrent under contact due to light can penetrate though into depletion region then generate photocurrent. ITO will prepare by RF sputtering technique and investigate material characteristics such as electrical and optical properties. Optimize ITO properties after various thickness by growth sputter time show high transparent around 91.2% with low resistance 3.4x10-3 ohm-cm. Build in voltage of device show 0.3V by same with metal contact and current under light exposure show around 1.5mA at 25,000 lux with bias -5V.

This article report the fabrication and characteristics of MSM photo detector by compare between non-doped and doped platinum (Pt) atom. Fabrication process has same but different in Pt doping process for atom doping and diffusion process. The metal finger width 2um with 50 um spacing between metal contact. At bias voltage 10 voltage show higher capacitance-voltage and photocurrent increase after doped with Pt atom. By experiment shows photocurrent increase around 4 times from 45.98 to 197.22 uA at bias 10 voltage by photoluminescence 25,000 lux.

The tellurite glasses doped with Nd3+ ion were prepared with the compositions (55-x)TeO2-10ZnF2-35BaO-xNd2O3 (where x = 0.00, 0.05, 0.10, 0.50 1.00 and 1.50 mol%) by the normal melt quenching technique and characterized the spectroscopic properties. The spectroscopic properties of tellurite glasses measured from the absorption and emission measurements with Judd-Ofelt analysis. The X-ray diffraction (XRD) pattern confirms the amorphous nature. UV-Vis-NIR absorption spectra of tellurite glasses divulged nine significant peaks. The absorption peaks slightly increase with increasing of Nd3+ concentration. The NIR emission spectra at 913, 1,069 and 1,341 nm have been registered for Nd3+ in tellurite glasses, which corresponds to the transitions originating from 4F3/2 level to the 4I9/2, 4I11/2 and 4I13/2 levels of Nd3+ ion, respectively, under the excitation of 523 nm. The results indicate that the prepared glass system could be a suitable candidate for using it as laser gain media around 1,069 nm.

In this paper will present the properties of PN diode before and after expose by radiation. Although, radiation help to improve the performance of semiconductor device but still has some damage in device structure. In previous article I have showed performance improve after expose by soft radiation. The device is exposed by low frequency X-ray radiation (soft radiation flash exposure: SRFE) technique with few second for several times. In principle of PN diode after fabrication will has defects from process such as ion implantation, doped and silicon wafer process. The results show temperature while SRFE expose on device that generate high temperature on surface and silicon boundary that may the optimize energy and expose time for treatment damage of PN diode.

Sodium gadolinium phosphate oxide and sodium gadolinium oxyfluoride glasses doped with europium oxide were prepared by melt-quenching technique. The physical, optical properties of the glass samples were studied. The density, molar volume and refractive index of the glass samples were carried out. Density and molar volume of oxide glass is more than oxyfluoride glass. The average phosphate to phosphate distance for oxide glass seems to be more than oxyfluoride glass. Polaron radius, inter-ionic radius shows 1.181 nm, 2.88 nm and 1.174 nm, 2.86 nm for oxide glass and oxyfluoride glasses respectively. Oxide electronic Polarizability and optical basicity of the oxide glass are lower than oxy-fluoride glass. Theoretical optical basicity shows higher for oxide glass than oxyfluoride suggesting increase in covalency of the cation to oxygen bonds in oxide glass. Optical band gap were estimated and found to be 3.061eV and 3.204 eV for oxide and oxyfluoride glass. Theoretical two photon absorption coefficient β were evaluated and found to be 11.96 and 10.80 for oxide and oxyfluoride glasses respectively. Furthermore, the glasses were subjected to study for their luminescence properties of the oxide and oxyfluoride glass samples.

In this study present the effect of soft radiation flash exposure (SRFE) to forward bias current-voltage (I-V) of PN diode by using COMSOL simulation program. The results show surface thermal and electric change while expose by radiation with flash exposure technique. Series resistance (Rs) increase around 2 times and close to idea case after expose by radiation, the radiation will impact to bulk defect and reduce surface recombination. SRFE induce temperature on surface and deep into silicon bulk. The value of Rs increase with increase expose time. The changing of Rs becomes independent from radiation dose at high forward bias voltage.

Nd3+ ion doped lithium aluminium phosphate glasses were synthesized and studied their properties for laser medium application. The density and the refractive index of the glass samples were carried out at the room temperature. The optical and luminescence properties were studied by investigating absorption and NIR emission spectra of the glass samples. The glasses absorbed photons in ultraviolet (UV), visible light (VIS) and near-infrared (NIR) regions are clearly observed from absorption spectra. For the photoluminescence properties, the glass samples showed the strongest emission at 1063 nm when it were excited by 581 nm which assigned to the energy transitions of Nd3+. The three phenomenological Judd-Ofelt parameters (Ω2, Ω4, Ω6) were determined from the spectral intensities of absorption band in order to calculate the radiative transition possibility (AR), stimulated emission cross section (σ(λp)) and branching ratio (βR) of the w4F3/2 → 4I9/2, 4I11/2 and 4I13/2 transitions. From the obtained results the conclusions made about the possibility of using these glasses as laser material.