Characterization of Novolac Based Photoresists to Fabricate 3D Polymer Dome Features

2005 ◽  
Author(s):  
Sriram Muthukumar ◽  
Tom W. Miller ◽  
Balu Pathangey ◽  
Neha M. Patel ◽  
Charles D. Hill
Keyword(s):  
Thermal Characteristics ◽  
Analytical Techniques ◽  
Gas Chromatography Mass Spectrometry ◽  
Solid Loading ◽  
Wafer Level ◽  
Final Size ◽  
Free Standing ◽  
Dome Formation ◽  
Size And Shape ◽  
Solvent Type

Wafer level, 3D, free standing structures (e.g., domes or hemi-cylinders) can be fabricated using polymer dome features as sacrificial templates for MEMS and interconnect applications. Understanding the kinetics of dome formation and the material properties are essential for a robust and manufacturable process of controlling the size and shape of the photoresist features. In this paper, temporal and thermal characteristics of Novolac based photoresists are presented as a function of solid loading and solvent type using analytical techniques such as Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) spectroscopy, hot stage microscopy, and Gas Chromatography/ Mass Spectrometry (GC/MS). The solid loading influences the thickness and processing ability of the resist. The solvent evaporation rate controls the final size and shape of the 3D polymer dome features. Solvent is the primary material lost during the dome formation and the onset of deformation is dependent on temperature and ramp rate.

scholarly journals Comparison of Three Approaches to Assess the Flavour Characteristics of Scotch Whisky Spirit

2021 ◽  
Vol 11 (4) ◽  
pp. 1410
Author(s):  
Martina Daute ◽  
Frances Jack ◽  
Irene Baxter ◽  
Barry Harrison ◽  
John Grigor ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Descriptive Analysis ◽  
Analytical Techniques ◽  
Gas Chromatography Mass Spectrometry ◽  
Multiple Factor Analysis ◽  
Quantitative Descriptive Analysis ◽  
Yeast Strains ◽  
Quantitative Descriptive ◽  
Scotch Whisky ◽  
Multiple Factor

This study compared the use of three sensory and analytical techniques: Quantitative Descriptive Analysis (QDA), Napping, and Gas Chromatography-Mass Spectrometry (GC-MS) for the assessment of flavour in nine unmatured whisky spirits produced using different yeasts. Hierarchical Multiple Factor Analysis (HMFA) showed a similar pattern of sample discrimination (RV scores: 0.895–0.927) across the techniques: spirits were mostly separated by their Alcohol by Volume (ABV). Low ABV spirits tended to have heavier flavour characteristics (feinty, cereal, sour, oily, sulphury) than high ABV spirits, which were lighter in character (fruity, sweet, floral, solventy, soapy). QDA differentiated best between low ABV spirits and GC-MS between high ABV spirits, with Napping having the lowest resolution. QDA was time-consuming but provided quantitative flavour profiles of each spirit that could be readily compared. Napping, although quicker, gave an overview of the flavour differences of the spirits, while GC-MS provided semi-quantitative ratios of 96 flavour compounds for differentiating between spirits. Ester, arenes and certain alcohols were found in higher concentrations in high ABV spirits and other alcohols and aldehydes in low ABV spirits. The most comprehensive insights on spirit flavour differences produced by different yeast strains are obtained through the application of a combination of approaches.

Cellular fatty acids of Peptococcus variabilis and Peptostreptococcus anaerobius

1977 ◽  
Vol 5 (6) ◽  
pp. 665-667
Author(s):  
C W Moss ◽  
M A Lambert ◽  
G L Lombard
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Gas Chromatography ◽  
Analytical Techniques ◽  
Gas Chromatography Mass Spectrometry ◽  
Cellular Fatty Acids ◽  
Chromatography Mass Spectrometry ◽  
Branched Chain

Cellular fatty acids of Peptococcus variables and Peptostreptococcus anaerobius were identified by gas chromatography, mass spectrometry, and associated analytical techniques. Iso- and anteiso-branched-chain acids were major components in both species.

scholarly journals Synthesis of Uniform Mesoporous Zeolite ZSM-5 Catalyst for Friedel-Crafts Acylation

2019 ◽  
Vol 3 (2) ◽  
pp. 35 ◽  
Author(s):  
Heman Smail ◽  
Mohammad Rehan ◽  
Kafia Shareef ◽  
Zainab Ramli ◽  
Abdul-Sattar Nizami ◽  
...  
Keyword(s):  
Surface Area ◽  
Surface Acidity ◽  
Analytical Techniques ◽  
Acid Sites ◽  
Zeolite Catalysts ◽  
Gas Chromatography Mass Spectrometry ◽  
Crystallographic Structure ◽  
Mesoporous Zeolite ◽  
Mesoporous Zeolites ◽  
Surfactant Templates

This work highlights how the treatment of ZSM-5 (parent Zeolite Socony Mobil–5, Si/Al = 23) with different surfactant templates and alkaline solution, improved the catalytic performance in the Friedel-Crafts acylation of anisole with a propionic anhydride to obtain p-methoxypropiophenone. The modified microporous to mesoporous zeolite catalysts were characterized using different analytical techniques, including X-ray diffraction (XRD), nitrogen porosimetry, Fourier-transform infrared spectroscopy (FT-IR), temperature-programmed desorption (ammonia-TPD) and field emission scanning electron microscopy (FE-SEM) to analyze the crystallographic structure, surface acidity, surface area, porosity, morphology, and particle size. The results showed that the formed mesoporous zeolite by NaOH solution had smaller mesopores (ca. 3.7 nm) as compared to the mesoporous zeolites obtained by surfactant templates, such as, CTAB (ca. 14.9 nm), TPAOH (ca. 11.1 nm) and mixture of CTAB/TPAOH (ca. 15.2 nm). The catalytic acylation reaction was conducted in a batch glass reactor at various temperatures and the products were analyzed using off-line gas chromatography–mass spectrometry (GC-MS). It was found that the activity of treated ZSM-5 with mixed surfactant templates (CTAB/TPAOH) exhibited enhanced selectivity towards the main product (p-methoxypropiophenone) by a factor 1.7 or higher than unmodified ZSM-5 due to its increased surface area by 1.5 times and enhanced acid sites.

Development of High Density RDL Technologies for Panel Level Processing

2019 ◽  
Vol 2019 (DPC) ◽  
pp. 000284-000313
Author(s):  
Lars Böttcher ◽  
S. Karaszkiewicz ◽  
F. Schein ◽  
R. Kahle ◽  
A. Ostmann
Keyword(s):  
Coefficient Of Thermal Expansion ◽  
High Density ◽  
Organic Films ◽  
High Yield ◽  
Wafer Level ◽  
Final Size ◽  
Process Yield ◽  
Cu Pillar ◽  
Thin Organic Films ◽  
Advanced Packaging

Advanced packaging technologies like wafer-level fan-out and 3D System-in-Packages (SIPs) are rapidly penetrating the market of electronic components. A recent trend to reduce cost is the extension of processes to large manufacturing formats, called Panel Level Packaging (PLP). In a consortium of German partners from industry and research advanced technologies for PLP are developed. The project aims for an integrated process flow for SIPs with chips embedded into an organic laminate matrix. At first dies with Cu pillar structures are placed into openings of a laminate frame layer with very low coefficient of thermal expansion (CTE). They are embedded by vacuum lamination of thin organic films, filling the very small gap down to 15 μm between chips and frame. The frame provides alignment marks for a local registration of following processes. The ridged frame limits die shift during embedding and gives a remarkable handling robustness. Developments are initially performed on a 305×256mm2 panel format, aiming for a final size of 610×615 mm2. On the top side of embedded chips, a 20μm dielectric film is applied. The goal is to avoid additional via formation and to realize a direct connection between the Cu pillar of the die and the RDL The RDL formation is based on semi-additive processing. Therefore a Ti or TiW barrier and Cu seed layer is sputtered. Subsequently a 7μm photoresist is applied and exposed by a newly developed Direct Imaging (DI) system. Lines and spaces of 4μm were achieved with high yield. In the following, Cu is simultaneously electroplated for the via contacts and interconnects traces. Finally, the photo resist is stripped and the TiW barrier and Cu seed layers are etched. The goal of the development is to provide a technology for a high-density RDL formation on large panel sizes. The paper will discuss the new developments in detail, e.g. the influence of most significant process parameters, like lithographical resolution, minimum via diameter and the placement and alignment accuracy on overall process yield.

Reliability Assessment and Failure Analysis of G-Helix, a Free-Standing Compliant Off-Chip Interconnect

2009 ◽  
Vol 6 (1) ◽  
pp. 59-65
Author(s):  
Karan Kacker ◽  
Suresh K. Sitaraman
Keyword(s):  
Failure Analysis ◽  
Dielectric Material ◽  
Organic Substrate ◽  
Wafer Level ◽  
Free Standing ◽  
Fine Pitch ◽  
Cross Section Area ◽  
Interconnect Reliability ◽  
Compliant Interconnect ◽  
Low K

Continued miniaturization in the microelectronics industry calls for chip-to-substrate off-chip interconnects that have 100 μm pitch or less for area-array format. Such fine-pitch interconnects will have a shorter standoff height and a smaller cross-section area, and thus could fail through thermo-mechanical fatigue prematurely. Also, as the industry transitions to porous low-K dielectric/Cu interconnect structures, it is important to ensure that the stresses induced by the off-chip interconnects and the package configuration do not crack or delaminate the low-K dielectric material. Compliant free-standing structures used as off-chip interconnects are a potential solution to address these reliability concerns. In our previous work we have proposed G-Helix interconnects, a lithography-based electroplated compliant off-chip interconnect that can be fabricated at the wafer level. In this paper we develop an assembly process for G-Helix interconnects at a 100 μm pitch, identifying the critical factors that impact the assembly yield of such free-standing compliant interconnect. Reliability data are presented for a 20 mm × 20 mm chip with G-Helix interconnects at a 100 μm pitch assembled on an organic substrate and subjected to accelerated thermal cycling. Subsequent failure analysis of the assembly is performed and limited correlation is shown with failure location predicted by finite elements models.

Technologies for Wafer Level MEMS Capping based on Permanent and Temporary Wafer Bonding

2015 ◽  
Vol 2015 (DPC) ◽  
pp. 000698-000725 ◽  
Author(s):  
Kai Zoschke ◽  
Klaus-Dieter Lang
Keyword(s):  
Wafer Bonding ◽  
Rf Mems ◽  
Electrical Contacts ◽  
Bonding Process ◽  
Frame Structure ◽  
Back Side ◽  
Wafer Level ◽  
Free Standing ◽  
Carrier Wafer ◽  
Base Substrate

Further cost reduction and miniaturization of electronic systems requires new concepts for highly efficient packaging of MEMS components like RF resonators or switches, quartz crystals, bolometers, BAWs etc. This paper describes suitable base technologies for the miniaturized, low-cost wafer level chip-scale packaging of such MEMS. The approaches are based on temporary handling and permanent bonding of cap structures using adhesives or solder onto passive or active silicon wafers which are populated with MEMS components or the MEMS wafer themselves. Firstly, an overview of the possible packaging configurations based on different types of MEMS is discussed where TSV based and non-TSV based packaging solutions are distinguished in general. The cap structure for the TSV based solution can have the same size as the MEMS carrying substrate, since the electrical contacts for the MEMS can be routed either thought the cap or base substrate. Thus, full format cap wafers can be used in a regular wafer to wafer bonding process to create the wafer level cavity packages. However, if no TSVs are present in the cap or base substrate, the cap structure needs to be smaller than the base chip, so that electrical contacts outside the cap area can be accessed after the caps were bonded. Such a wafer level capping with caps smaller than the corresponding base chips can be obtained in two ways. The first approach is based on fabrication and singulation of the caps followed by their temporary face up assembly in the desired pattern on a help wafer. In a subsequent wafer to wafer bonding sequence all caps are transferred onto the base wafer. Finally the help wafer is removed from the back side of the bonded caps. This approach of reconfigured wafer bonding is especially used for uniform cap patterns or, if MEMS have an own bond frame structure. In that case no additional cap is required, since the MEMS can act as their own cap. The second approach is based on cap structure fabrication using a compound wafer stack consisting of two temporary bonded wafers. One wafer acts as carrier wafer whereas the other wafer is processed to form cap structures. Processes like thinning, silicon dry etching, deposition and structuring of polymer or metal bonding frames are performed to generate free-standing and face-up directed cap structures. The so created “cap donor wafer” is used in a wafer to wafer bonding process to bond all caps permanently to the corresponding MEMS base wafer. Finally, the temporary bonded carrier wafer is removed from the backside of the transferred caps. With that approach a fully custom specific and selective wafer level capping is possible featuring irregular cap patterns and locations on the MEMS base wafer. Examples like the selective capping process for RF MEMS switches are presented and discussed in detail. All processes were performed at 200mm wafer level.

scholarly journals Excretion and Detection of Cathinone, Cathine, and Phenylpropanolamine in Urine after Kath Chewing

2002 ◽  
Vol 48 (10) ◽  
pp. 1715-1719 ◽  
Author(s):  
Stefan W Toennes ◽  
Gerold F Kauert
Keyword(s):  
Analytical Techniques ◽  
Urine Samples ◽  
Gas Chromatography Mass Spectrometry ◽  
Fluorescence Polarization Immunoassay ◽  
Photodiode Array Detection ◽  
Negative Results ◽  
Specificity And Sensitivity ◽  
Photodiode Array ◽  
Array Detection ◽  
Positive Results

Abstract Introduction: The stimulating herbal drug kath is uncommon in most countries, and information on its detection and interpretation of analytical results is limited. Therefore, a study with kath was carried out to compare the efficiencies of different analytical techniques used to detect drug use. Methods: Four volunteers chewed kath leaves for 1 h; urine samples were collected up to 80 h afterward and analyzed by the Abbott fluorescence polarization immunoassay (FPIA), the Mahsan-AMP300 on-site immunoassay, the Bio-Rad Remedi HS HPLC system with photodiode array detection (DAD), and gas chromatography–mass spectrometry (GC-MS). Results: FPIA gave negative results, whereas positive results were obtained with the Mahsan test during the first day. With HPLC, one peak could be observed up to 50 h, but its DAD spectrum could not be identified by the system. Further investigations indicated that the kath alkaloids coeluted and produced a mixed DAD spectrum. With GC-MS, the specific kath ingredient cathinone was detected up to 26 h, whereas cathine and norephedrine were still detectable in the last samples. Maximum concentrations of cathinone, cathine, and norephedrine in urine samples from the study were 2.5, 20, and 30 mg/L, respectively, whereas in authentic cases the concentrations were much higher. Conclusion: GC-MS is superior to the screening techniques Mahsan-AMP300 and Remedi with respect to specificity and sensitivity for the detection of kath use in urine.

scholarly journals Quantitative Characteristics of Toxic Compounds According to the Solvent Type

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Young-Ji An ◽  
Seong-Jin Choi ◽  
Yong-Hyun Kim ◽  
Kyuhong Lee
Keyword(s):  
Quantitative Analysis ◽  
Analytical Data ◽  
Gas Chromatography Mass Spectrometry ◽  
Toxic Compounds ◽  
Solvent Type ◽  
Target Analytes ◽  
Relative Standard ◽  
Rf Values ◽  
Benzene Toluene ◽  
Working Standards

The quantitative analysis of target substances is an important part of assessing the toxicity of diverse materials. Usually, the quantitation of target compounds is conducted by instrumental analysis such as chromatography and capillary electrophoresis. If solvents are used in the pretreatment step of the target analyte quantification, it would be crucial to examine the solvent effect on the quantitative analysis. Therefore, in this study, we assessed the solvent effects using four different solvents (methanol, hexane, phosphate buffered saline (PBS), and dimethyl sulfoxide (DMSO)) and three toxic compounds (benzene, toluene, and methylisothiazolinone (MIT)). Liquid working standards containing the toxic compounds were prepared by dilution with each solvent and analyzed by gas chromatography-mass spectrometry (GC-MS). As a result, we found that the response factor (RF) values of the target analytes were different, depending on the solvent types. In particular, benzene and toluene exhibited their highest RF values (33,674 ng−1 and 78,604 ng−1, respectively) in hexane, while the RF value of MIT was the highest (9,067 ng−1) in PBS. Considering the correlation (R2) and relative standard deviation (RSD) values, all target analytes showed fairly good values (R2 > 0.99 and RSD < 10%) in methanol and DMSO. In contrast, low R2 (0.0562) and high RSD (10.6%) values of MIT were detected in hexane, while benzene and toluene exhibited relatively low R2 and high RSD values in PBS (mean R2 = 0.9892 ± 0.0146 and mean RSD = 13.3 ± 4.1%). Based on these findings, we concluded that the results and reliability of the quantitative analysis change depending on the analyte and solvent types. Therefore, in order to accurately assess the toxicity of target compounds, reliable analytical data should be obtained, preferentially by considering the solvent types.

Reliable Design of TSV in Free-Standing Wafers and 3D Integrated Packages

2011 ◽  
Author(s):  
Xi Liu ◽  
Margaret Simmons-Matthews ◽  
Kurt P. Wachtler ◽  
Suresh K. Sitaraman
Keyword(s):  
Integrated Circuit ◽  
Mechanical Performance ◽  
Semiconductor Industry ◽  
Three Dimensional ◽  
Wafer Level ◽  
Free Standing ◽  
Design Factor ◽  
Reliable Design ◽  
Reliability Issue ◽  
Key Enabling Technologies

Through-silicon via (TSV), being one of the key enabling technologies for three dimensional (3D) Integrated Circuit (IC) stacking, silicon interposer technology, and advanced wafer level packaging (WLP), has attracted tremendous interest throughout the semiconductor industry. However, limited work addresses TSV reliability issue, and most of the existing reliability studies focus on the thermo-mechanical performance of TSVs in a free-standing wafer, rather than in an integrated package. In this paper, three-dimensional thermomechanical Finite-Element (FE) models with TSVs in both free-standing wafers and 3D integrated packages have been built and analyzed. In addition, Design of Experiments (DOE) based approach has been used to understand the effect of various parameters. Results show that the selection of underfill materials between stacked dies is the most dominating design factor for TSV/microbump reliability.

Sign in / Sign up

Export Citation Format

Share Document