Microwave Plasma Assisted Aerosol Deposition (μ-PAD) for Ceramic Coating Applications

To improve plasma and chemical resistance on various vacuum components used for semiconductor manufacturing equipment, various ceramic coating techniques have been applied. Among these methods for ceramic coating, the well-known atmospheric plasma spray (APS) is advantageous for providing thick film (100 µm or more) deposition. However, there are problems associated with the phase transition of the coating film and poor film quality due to formation of voids. To solve these problems, the aerosol deposition (AD) method has been developed. This method provides nice ceramic film quality. However, the coating rate is quite slow and has difficulty producing thick films (>30 µm). To overcome these limitations, microwave plasma-assisted aerosol deposition (μ-PAD) is applied at low vacuum conditions without the AD nozzle. This method uses a microwave plasma source during the AD process. After enduring a long-term durability test, as a trial run, μ-PAD has been applied on the actual process site. With the Al2O3 powder, μ-PAD shows a coating rate that is 12 times higher than the AD method. In addition, the formation of a thicker film (96 µm) deposition has been demonstrated. On the other hand, the coating film hardness, porosity, adhesion, and withstand voltage characteristics were confirmed to be less than the AD method

Microwave Plasma Assisted Aerosol Deposition (μ-PAD) for Ceramic Coating Applications

To improve plasma and chemical resistance on various vacuum components used for semiconductor manufacturing equipment, various ceramic coating techniques have been applied. Among these methods for ceramic coating, the well-known atmospheric plasma spray (APS) is advantageous for providing thick film (100 µm or more) deposition. However, there are problems associated with the phase transition of the coating film and poor film quality due to formation of voids. To solve these problems, the aerosol deposition (AD) method has been developed. This method provides nice ceramic film quality. However, the coating rate is quite slow and has difficulty producing thick films (>30 µm). To overcome these limitations, microwave plasma-assisted aerosol deposition (μ-PAD) is applied at low vacuum conditions without the AD nozzle. This method uses a microwave plasma source during the AD process. After enduring a long-term durability test, as a trial run, μ-PAD has been applied on the actual process site. With the Al2O3 powder, μ-PAD shows a coating rate that is 12 times higher than the AD method. In addition, the formation of a thicker film (96 µm) deposition has been demonstrated. On the other hand, the coating film hardness, porosity, adhesion, and withstand voltage characteristics were confirmed to be less than the AD method

Characteristics of Plasma Flow for Microwave Plasma Assisted Aerosol Deposition

To validate the possibility of the developed microwave plasma source with a novel structure for plasma aerosol deposition, the characteristics of the plasma flow velocity generated from the microwave plasma source were investigated by a Mach probe with pressure variation. Simulation with the turbulent model was introduced to deduce calibration factor of the Mach probe and to compare experimental measurements for analyses of collisional plasma conditions. The results show calibration factor does not seem to be a constant parameter and highly dependent on the collision parameter. The measured plasma flow velocity, which witnessed fluctuations produced by a shock flow, was between 400 and 700 m/s. The optimized conditions for microwave plasma assisted aerosol deposition were derived by the results obtained from analyses of the parameters of microwave plasma jet. Under the optimized conditions, Y2O3 coatings deposited on an aluminum substrate were investigated using scanning electron microscope. The results presented in this study show the microwave plasma assisted aerosol deposition with the developed microwave plasma source is highly feasible for thick films with >50 μm

Regulation of Chitinase-3-like-1 in T cell elicits Th1 and cytotoxic responses to inhibit lung metastasis

Chitinase-3-like-1 (Chi3l1) is known to play a significant role in the pathogenesis of Type 2 inflammation and cancer. However, the function of Chi3l1 in T cell and its clinical implications are largely unknown. Here we show that Chi3l1 expression was increased in activated T cells, especially in Th2 cells. In addition, Chi3l1-deficient T cells are hyper-responsive to TcR stimulation and are prone to differentiating into Th1 cells. Chi3l1-deficient Th1 cells show increased expression of anti-tumor immunity genes and decreased Th1 negative regulators. Deletion of Chi3l1 in T cells in mice show reduced melanoma lung metastasis with increased IFNγ and TNFα-producing T cells in the lung. Furthermore, silencing of Chi3l1 expression in the lung using peptide-siRNA complex (dNP2-siChi3l1) efficiently inhibit lung metastasis with enhanced Th1 and CTL responses. Collectively, this study demonstrates Chi3l1 is a regulator of Th1 and CTL which could be a therapeutic target to enhance anti-tumor immunity.1

Association study between single nucleotide polymorphisms in promoter region of AVPR1A and Korean autism spectrum disorders

To determine the association between arginine vasopressin receptor 1A gene (AVPR1A)and autism spectrum disorders (ASDs), we examined 3 single nucleotide polymorphisms (SNPs), namely, rs7294536, rs3759292, and rs10877969, in the promoter region of AVPR1A by using a family-based association test (FBAT) in 151 Korean trios. Our results demonstrated a statistically significant association between autism and SNPs (additive model: rs7294536, chi(2)=9.328, df=2, P=0.002: rs10877969, chi(2)=11.529, df=2, P<0.001) as well as between autism and haplotype analysis (additive model: chi(2)=14.122, df=3,P=0.003). In addition, we found that ADI-R scores calculated by using a diagnostic algorithm for failure to develop peer relationships (A2) were higher in subjects having the AA genotype than in subjects having the AG and GG genotypes of rs7294536. Thus, our study provides evidence for a possible association between these SNPs and the phenotype of ASDs. (C) 2010 Elsevier Ireland Ltd. All rights reserved.This study was supported by grants from the Korea Healthcare Technology R&D Project, Ministry of Health &Welfare, Republic of Korea (A080651) and the Korea Research Foundation Grant funded by the Korean Government (MOEHRD, Basic Research Promotion Fund) (KRF-2008-331-C00226).Yang SY, 2010, PSYCHIAT RES, V178, P199, DOI 10.1016/j.psychres.2009.11.007Nicholas JS, 2009, ANN EPIDEMIOL, V19, P808, DOI 10.1016/j.annepidem.2009.04.005Levin R, 2009, PSYCHONEUROENDOCRINO, V34, P901, DOI 10.1016/j.psyneuen.2008.12.014Baron-Cohen S, 2009, BRIT J PSYCHIAT, V194, P500, DOI 10.1192/bjp.bp.108.059345Bora E, 2009, CURR OPIN PSYCHIATR, V22, P320, DOI 10.1097/YCO.0b013e328329e970Yoo HJ, 2009, NEUROSCI RES, V63, P172, DOI 10.1016/j.neures.2008.11.007Walum H, 2008, P NATL ACAD SCI USA, V105, P14153, DOI 10.1073/pnas.0803081105Yoo HJ, 2008, NEUROSCI RES, V62, P66, DOI 10.1016/j.neures.2008.05.008Chen J, 2008, EXP NEUROL, V211, P529, DOI 10.1016/j.expneurol.2008.02.023Pardo CA, 2007, BRAIN PATHOL, V17, P434, DOI 10.1111/j.1750-3639.2007.00102.xKim SA, 2007, NEUROSCI RES, V58, P332, DOI 10.1016/j.neures.2007.03.002Ma DQ, 2007, MOL PSYCHIATR, V12, P376, DOI 10.1038/sj.mp.4001927Cho IH, 2007, BRAIN RES, V1139, P34, DOI 10.1016/j.brainres.2007.01.002YOO HJ, 2007, KOREAN VERSION AUTISPRICHARD ZM, 2007, HUM MUTAT, V28, P1150KNAFO A, 2007, GENES BRAIN BEHAV, V7, P266Persico AM, 2006, TRENDS NEUROSCI, V29, P349, DOI 10.1016/j.tins.2006.05.010Yirmiya N, 2006, MOL PSYCHIATR, V11, P488, DOI 10.1038/sj.mp.4001812EGASHIRA N, 2006, NIHON SHINKEI SEISHI, V26, P101Hammock EAD, 2005, GENES BRAIN BEHAV, V4, P289Hammock EAD, 2005, SCIENCE, V308, P1630, DOI 10.1126/science.1111427Wassink TH, 2004, MOL PSYCHIATR, V9, P968, DOI 10.1038/sj.mp.4001503Kim SJ, 2002, MOL PSYCHIATR, V7, P503, DOI 10.1038/sj.mp.4001125Chevaleyre V, 2002, J NEUROSCI, V22, P265Folstein SE, 2001, NAT REV GENET, V2, P943Son MC, 2001, NEUROBIOL LEARN MEM, V76, P388, DOI 10.1006/nlme.2001.4020Horvath S, 2001, EUR J HUM GENET, V9, P301Hurbin A, 1998, ENDOCRINOLOGY, V139, P4701QIAO LY, 1998, ZHONGGUO YAO LI XUE, V19, P15BAILEY A, 1995, PSYCHOL MED, V25, P63*ASS AM PSYCH, 1994, DIAGN STAT MAN MENTVANDENHOOFF P, 1989, BRAIN RES, V505, P181