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Detournay A.,University of Lille Nord de France | Detournay A.,Ecole Des Mines de Douai | Sauvage S.,University of Lille Nord de France | Sauvage S.,Ecole Des Mines de Douai | And 11 more authors.
Journal of Environmental Monitoring | Year: 2011

Studies have shown that biogenic compounds, long chain secondary compounds and long lifetime anthropogenic compounds are involved in the formation of organic aerosols in both polluted areas and remote places. This work aims at developing an active sampling method to monitor these compounds (i.e. 6 straight-chain saturated aldehydes from C6 to C11; 8 straight-chain alkanes from C9 to C16; 6 monoterpenes: α-pinene, β-pinene, camphene, limonene, α-terpinene, & γ-terpinene; and 5 aromatic compounds: toluene, ethylbenzene, meta-, para- and ortho-xylenes) in remote areas. Samples are collected onto multi-bed sorbent cartridges at 200 mL min-1 flow rate, using the automatic sampler SyPAC (TERA-Environnement, Crolles, France). No breakthrough was observed for sampling volumes up to 120 L (standard mixture at ambient temperature, with a relative humidity of 75%). As ozone has been shown to alter the samples (losses of 90% of aldehydes and up to 95% of terpenes were observed), the addition of a conditioned manganese dioxide (MnO 2) scrubber to the system has been validated (full recovery of the affected compounds for a standard mixture at 50% relative humidity - RH). Samples are first thermodesorbed and then analysed by GC/FID/MS. This method allows suitable detection limits (from 2 ppt for camphene to 13 ppt for octanal - 36 L sampled), and reproducibility (from 1% for toluene to 22% for heptanal). It has been successfully used to determine the diurnal variation of the target compounds (six 3 h samples a day) during winter and summer measurement campaigns at a remote site in the south of France. © The Royal Society of Chemistry.

Hayeck N.,Aix - Marseille University | Gligorovski S.,Aix - Marseille University | Poulet I.,TERA Environnement | Wortham H.,Aix - Marseille University
Talanta | Year: 2014

To prevent the degradation of the device characteristics it is important to detect the organic contaminants adsorbed on the wafers. In this respect, a reliable qualitative and quantitative analytical method for analysis of semi-volatile organic compounds which can adsorb on wafer surfaces is of paramount importance. Here, we present a new analytical method based on Wafer Outgassing System (WOS) coupled to Automated Thermal Desorber-Gas chromatography-Mass spectrometry (ATD-GC-MS) to identify and quantify volatile and semi-volatile organic compounds from 6, 8 and 12 wafers. WOS technique allows the desorption of organic compounds from one side of the wafers. This method was tested on three important airborne contaminants in cleanroom i.e. tris-(2-chloroethyl) phosphate (TCEP), tris-(2-chloroisopropyl) phosphate (TCPP) and diethyl phthalate (DEP). In addition, we validated this method for the analysis and quantification of DEP, TCEP and TCPP and we estimated the backside organic contamination which may contribute to the front side of the contaminated wafers. We are demonstrating that WOS/ATD-GC-MS is a suitable and highly efficient technique for desorption and quantitative analysis of organophosphorous compounds and phthalate ester which could be found on the wafer surface. © 2014 Elsevier B.V.

Pic N.,STMicroelectronics | Martin C.,STMicroelectronics | Vitalis M.,STMicroelectronics | Calarnou T.,STMicroelectronics | And 6 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

A case study of drastic photolithography defectivity reduction on i-line and Deep-UV (DUV) tools is presented. We show how this result is linked with reduction of Airborne Molecular Contamination (AMC) in clean room by combined installation of novel type of filters on tracks and on the recirculation air treatment. The root cause was identified to be the presence of acetic acid in clean room created by a reaction with the filters (mounted on track tools to exclude ammonia contamination of the process) and the photo solvent itself (here mainly 1-methoxy-2-propanol acetate: PGMEA). Crucial for the project success was the use of a real time monitoring tool to detect the sources of Volatile Organic Compounds (VOC). Finally, a model of chemical reaction of satellite defects creation is discussed based on a Time of Flight Static SIMS (TOF SSIMS) analysis together with new AMC specification for acetic acid for the photolithography area. © 2010 Copyright SPIE - The International Society for Optical Engineering.

Hayeck N.,Aix - Marseille University | Temime-Roussel B.,Aix - Marseille University | Gligorovski S.,Aix - Marseille University | Mizzi A.,Aix - Marseille University | And 7 more authors.
International Journal of Mass Spectrometry | Year: 2015

The organic contamination has been recently considered as the most important problem for the photolithography world in the semiconductor industry, especially when the photolithographic methods moved from 130 nm node to 32 nm node. One of the most common organic compounds found in photolithography areas of the clean room is Trimethylsilanol (TMS), which can adsorb on the optical lenses forming a thin molecular layer, hence causing damages. Salt crystal formation is another potential threat for the optical devices. In the clean rooms, this salt is produced by a light-induced reaction between ammonia and an acid. In the context of semiconductor industry, the involved acid is usually the acetic acid produced by hydrolysis from propylene glycol methyl ether acetate (PGMEA), a commonly used organic compound in the photolithography. Here, we present an innovative analytical method using a state-of-the-art proton-transfer reaction-time-of-flight-mass spectrometer (PTR-ToF-MS) for on-line and continuous survey of volatile organic compounds (VOCs) with an emphasis on TMS and PGMEA. The effect of relative humidity on the detection and fragmentation of these organic compounds was assessed. The new analytical method is operated in a real life clean room environment and the results were compared with those obtained with off-line measurements using automated thermal desorber-gas chromatography-mass spectrometry (ATD-GC-MS) as reference method. The contamination sources were detected and identified, which is of paramount importance for the microelectronic fabrication plant. The trapping efficiency of the chemical filters used for AMCs filtration in the photolithography zone was determined. © 2015 Elsevier B.V. All rights reserved.

Poulhet G.,University of Lille Nord de France | Dusanter S.,University of Lille Nord de France | Dusanter S.,Indiana University Bloomington | Crunaire S.,University of Lille Nord de France | And 5 more authors.
Building and Environment | Year: 2014

While indoor air quality issues have received increasing attention the past decades, detailed investigations of primary sources of indoor pollution are still difficult to carry out. There is a lack of analytical tools and measurement procedures to identify sources of pollutants and to characterize their emissions. Formaldehyde is aubiquitous pollutant in indoor environments, which is known to lead to adverse health effects. This study describes a measurement procedure to apportion formaldehyde emissions from building and furnishing materials and presents a source apportionment study performed in French public schools. More than 29 sources of formaldehyde were characterized in each investigated classroom, with higher emissions from building materials compared to furnishing materials. Formaldehyde emission rates measured using passive flux samplers (PFS) range from 1.2 to 252μg/m2/h, highlighting several strong emitters made of wood products and foam. Interestingly, the ceiling was identified as the main source of formaldehyde in most classrooms. Measured emissions and air exchange rates were constrained in a mass balance model to evaluate the impact of formaldehyde reduction strategies. These results indicate that formaldehyde concentrations can be reduced by 87-98% by removing or replacing the main source of emission by a less emissive material and by increasing the air exchange rate to 1h-1. In addition, an intercomparison of total emissions calculated from (1) PFS measurements and from (2) measured formaldehyde concentrations and air exchange rates indicate that an unidentified sink of formaldehyde may exist in indoor environments. © 2013 Elsevier Ltd.

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