Impact Of Plasma Treatment Research Articles

Impact of remote plasma treatment on natural microbial load and quality parameters of selected herbs and spices

The decontamination efficiency of a non-thermal remote plasma application for dry and heat sensitive products was investigated. Therefore three different types of herbs and spices (pepper seeds, crushed oregano and paprika powder) with various surface-to-volume ratios were treated with plasma processed air up to 90min and the inactivation of their native microbial flora was examined. Furthermore the impact of the plasma treatment on the product color was determined. The remote plasma treatment reduced the native microbial flora of the pepper seeds and the paprika powder by more than 3log10 after 60min treatment time. However remote plasma treatment of red paprika powder resulted in a considerable loss of redness after a treatment time of ⩾5min. The lower inactivation of the native microbial flora of oregano of 1.6log10, was related to the much lower initial microbial load. The treatment had only a minor impact on the pepper seed’s and oregano’s color (ΔE∗ up to 10.2 and 20.0, respectively).

Impact of plasma treatment on electrical properties of TiO2/RuO2 based DRAM capacitor

In this work, we systematically studied the influence of the plasma treatment (PT) on the structural and electrical properties of Pt/rutile-TiO2/RuO2 metal–insulator–metal capacitors. The leakage current of the 12 nm thick TiO2 dielectrics prepared by atomic layer deposition was reduced below 10−7 A cm−2 while the capacitance equivalent thickness was kept below 0.5 nm using oxygen PT of the bottom RuO2 electrode. Reflection high energy electron diffraction, transmission electron microscopy, atomic force microscopy and x-ray photoelectron spectroscopy analyses allowed the conclusion that O2 plasma smoothened the RuO2 surface and increased its oxygen content through plasma induced surface reconstruction. The nucleation of TiO2 on the plasma-treated surface was faster while the thickness of the capacitor dead layer at the TiO2/RuO2 interface was reduced.

Viability of Human Blood Leukocytes Compared with Their Respective Cell Lines after Plasma Treatment

Non-thermal plasma application has become a promising field of investigation in chronic wound healing research over the past few decades. In addition to its well-characterized antibacterial effects, plasma potentially promotes the growth of eukaryotic cells. To date, mainly epithelial skin cells have been examined regarding the impact of plasma treatment on chronic wound healing. However, immune cells also are involved in wound healing as well as the removal of pathogens. Therefore, we compared the survival behavior of 2 human leukocyte cell lines (a monocyte and a CD4+ T helper cell line) and their respective human blood counterparts after exposure to plasma. Measurements of early and late apoptotic cells demonstrate that freshly isolated blood cells were more susceptible to apoptosis induction than the cell lines. Furthermore, blood and cell line monocytes tolerated longer plasma exposure compared with blood and cell line CD4+ T helper cells.

Impact of plasma treatment on structure and electrical properties of porous low dielectric constant SiCOH material

Low dielectric constant (low-k) porous films are needed for advanced technologies to improve signal propagation. The integration of porous low-k films faces more severe challenges due to the presence of porosity. Plasma treatments have been considered to be critical steps to impact the low-k films' properties. In this study, the effect of various H2/He plasma treatments on the porous low-k dielectrics deposited by plasma enhanced chemical vapor deposition was investigated. All the plasma treatments resulted in the formation of a thin and dense layer on the surface of the porous low-k films. Additionally, the properties of this top dense layer are modified and changed for the standard H2/He plasma treatment, leading to a degraded electrical and reliability performance. However, H2/He plasma-treated low-k dielectric by the remote plasma method shows a better electrical and reliability performance. As a result, the remote plasma treatment on the porous low-k dielectrics appears to be a promising method in the future interlayer dielectrics application.