Plasma-enhanced atomic layer deposition of Co using Co(MeCp)_2 precursor

Cobalt （Co） thermal or plasma enhanced atomic layer deposition （PE-ALD） was investigated using a novel metal organic precursor, Co（MeCp）2, and NH3 or H2 or their plasma as a reactant. The growth characteristics, electrical and microstructural properties were investigated. Especially, PE-ALD produced Co thin films at low growth temperature down to 100℃. Interestingly, the low temperature growth of Co films showed the formation of columnar structure at substrate temperature below 300℃. The growth characteristics and films properties of PE-ALD Co using bis（η-methylcyclopentadienyl） Co（II） （Co（MeCp）2） was compared with those of PE-ALD Co using other Cp based metal organic precursors, bis-cyclopentadienyl cobalt （II） （CoCp2） and cyclopentadienyl isopropyl acetamidinato-cobalt （Co（CpAMD））.

Preparation and properties of solution-processed zinc tin oxide films from a new organic precursor

Transparent,smooth and dense zinc tin oxide (ZTO) thin films have been successfully produced by using a new precursor solution,zinc acetate and tin(II) 2-ethylhexanoate mixed with 2-ethanolamine in methoxyethanol.The ZTO films have been prepared by spin-coating,followed by thermal treatment in oxygen atmosphere.The morphology,composition,crystallinity and band gap energy (Eg) of the ZTO thin films have been characterized by Atomic Force Microscopy (AFM),Atomic Emission Spectrometry (AES),X-ray Diffraction (XRD) and UV-vis spectrophotometry.The conductivity of ZTO is about 9.8×10-9 S/cm,as estimated from the current-voltage (I-V) curve.The effect of the thermal treatment process on the morphology of ZTO thin films is also discussed.

A field investigation into the characteristics and formation mechanisms of particles during the operation of laser printers and photocopiers

Indoor particle release from toner printing equipment (TPE) is a major health concern and has received wide attention.In this study,nine printing centers were randomly selected and three working phases were simulated,namely,non-working,normal printing/copying,and heavy printing/copying.The dynamics of the ozone (O_(3)),volatile organic compound (VOC),and particle emissions from TPE were determined by portable detectors.Results showed that particles,VOCs,and O_(3)were indeed discharged,and particles and VOCs concentrations remained at high levels.Among them,44%of the rooms represented high-level particle releases.Submicrometer-sized particles,especially nanoparticles,were positively correlated with VOCs,but were inversely proportional to the O_(3)concentration.Four elements,Ca,Al,Mg and Ni,were usually present in nanoparticles because of the discharge of paper.Si,Al,K,Ni and Pb were found in the submicrometer-sized particles and were consistent with the toner composition.The potential particle precursors were identified,which suggested that styrene was the most likely secondary organic aerosol (SOA) precursor.Overall,the use of the toner formulation and the discharge of paper attribute to the TPE-emitted particles,in which styrene is a specific monitoring indicator for the formation of SOA.