Jin Nyoung Jang

Oxygen elimination effect in silicon thin film by neutral beam assisted CVD system at room temperature

Solar cells with multi-junction structures employing various band gap layers are nowadays issue to achieve higher efficiency. We have prepared neutral beam assisted CVD (NBaCVD) deposited a-Si:H which has different oxygen contents as reflector bias and termination capacitor. The oxygen supplied by sputtering of quartz tube(shied for internal ICP antenna) as control of self bias. To control self sputtering of quartz we attached optimized valued capacitor between ends of antenna and ground. As increase of reflector bias directly related the energy of hydrogen, which is reflected from reflector, is increase then the oxygen contents reduced and transform the film structure as amorphous to nano-crystalline. The FTIR, XPS, optical band gap show the changes of oxygen and a-Si:H state as effect of energetic hydrogen reaction with oxygen and Six-Hy bond.

Post-annealing-free, room temperature processed nanocrystalline indium tin oxide thin films for plastic electronics

In this study, we confirm that bombardment by high energy negative oxygen ions (NOIs) is the key origin of electro-optical property degradations in indium tin oxide (ITO) thin films formed by conventional plasma sputtering processes. To minimize the bombardment effect of NOIs, which are generated on the surface of the ITO targets and accelerated by the cathode sheath potential on the magnetron sputter gun (MSG), we introduce a magnetic field shielded sputtering (MFSS) system composed of a permanent magnetic array between the MSG and the substrate holder to block the arrival of energetic NOIs. The MFSS processed ITO thin films reveal a novel nanocrystal imbedded polymorphous structure, and present not only superior electro-optical characteristics but also higher gas diffusion barrier properties. To the best of our knowledge, no gas diffusion barrier composed of a single inorganic thin film formed by conventional plasma sputtering processes achieves such a low moisture permeability.

New approaches for high doping and high crystal fraction in the mixed phase nano-crystal silicon thin film with low angle laterally grown grain by near room temperature deposition process with neutral beam assisted CVD

The NBaCVD system can control the crystalline phase and the doping efficiency simultaneously by the energy of impinge neutral particles. During the deposition process, energetic H-neutral atoms transport their energy to the surface of depositing film to enhance crystallization (crystal volume fraction (Xc) ~85%) and dopant activation (~1*1020 #/cm3, ~30 cm2/Vs) with low H ratio at near room temperature on the substrate. Also the increase of H enhance transport path (mobility incensement) which is deduced from transition of crystal orientation from [111] to [311] at constant Xc. The various analysis data of the thin films (CAFM, GIWAXS) represent the evidence of obvious flat-type nc embedded pm phase, and grain dominant charge transport characteristics.

Low Temperature Deposition a-SiNx:H Using ICP Source

The silicon nitride films were prepared by chemical vapor deposition using inductively coupled plasma. During the deposition, the substrate was heated at and power 1,000 W. To evolution low temperature manufacture, we have studied the role of source gases, , , , and , to produce Si-N and N-H bond in a-SiNx:H film growth. , , and flow rate fixed at 100, 10, and 10 sccm, flow rate varied from 0 to 10 sccm by small scale. To get the electrical characteristics, we makes MIM structure, and analysis surface bonding state. Experimental data show that Si-N and N-H bond is increased and hence electrical characteristics is showed 3 MV/cm breakdown-voltage, and leakage-current .