scholarly journals A Novel Manufacturing Process for Glass THGEMs and First Characterisation in an Optical Gaseous Argon TPC

2021 ◽  
Vol 11 (20) ◽  
pp. 9450
Author(s):  
Adam Lowe ◽  
Krishanu Majumdar ◽  
Konstantinos Mavrokoridis ◽  
Barney Philippou ◽  
Adam Roberts ◽  
...  
Keyword(s):  
Indium Tin Oxide ◽  
Manufacturing Process ◽  
Moisture Absorption ◽  
Fused Silica ◽  
Thickness Variation ◽  
Abrasive Machining ◽  
Light Production ◽  
Total Thickness Variation ◽  
Hexagonal Hole ◽  
Ductile Substrate

This paper details a novel, patent pending, abrasive machining manufacturing process for the formation of sub-millimetre holes in THGEMs, with the intended application in gaseous and dual-phase TPCs. Abrasive machining favours a non-ductile substrate such as glasses or ceramics. This innovative manufacturing process allows for unprecedented versatility in THGEM substrates, electrodes, and hole geometry and pattern. Consequently, THGEMs produced via abrasive machining can be tailored for specific properties: for example, high stiffness, low total thickness variation, radiopurity, moisture absorption/outgassing and/or carbonisation resistance. This paper specifically focuses on three glass substrate THGEMs (G-THGEMs) made from Schott Borofloat 33 and fused silica. Circular and hexagonal hole shapes are also investigated. The G-THGEM electrodes are made from indium tin oxide (ITO), with a resistivity of 150 Ω/Sq. All G-THGEMs were characterised in an optical (EMCCD) readout GArTPC and compared to a traditionally manufactured FR4 THGEM, with their charging and secondary scintillation (S2) light production behaviour analysed.

Study of Flow Boiling Characteristics of a Microchannel Using High Speed Visualization

2013 ◽  
Vol 135 (8) ◽  
Author(s):  
Rashid Ali ◽  
Björn Palm ◽  
Claudi Martin-Callizo ◽  
Mohammad H. Maqbool
Keyword(s):  
Heat Flux ◽  
Flow Pattern ◽  
Indium Tin Oxide ◽  
High Speed ◽  
Liquid Velocity ◽  
Flow Boiling ◽  
Fused Silica ◽  
Internal Diameter ◽  
Electrically Conductive ◽  
Heated Length

This paper presents the visualization results obtained for an experimental study of R134a during flow boiling in a horizontal microchannel. The microchannel used was a fused silica tube having an internal diameter of 781 μm, a heated length of 191 mm, and was coated with a thin, transparent, and electrically conductive layer of indium-tin-oxide (ITO) on the outer surface. The operating parameters during the experiments were: mass flux 100–400 kg/m2 s, heat flux 5–45 kW/m2, saturation temperatures 25 and 30 °C, corresponding to saturation pressures of 6.65 bar and 7.70 bar and reduced pressures of 0.163 and 0.189, respectively. A high speed camera with a close up lens was used to capture the flow patterns that evolved along the channel. Flow pattern maps are presented in terms of the superficial gas and liquid velocity and in terms of the Reynolds number and vapor quality plots. The results are compared with some flow pattern maps for conventional and micro scale channels available in the literature. Rigorous boiling and increased coalescence rates were observed with an increase in the heat flux.

Atomic Oxygen Plasma Effects on Cvd Deposited Diamond-Like Carbon Films

1991 ◽  
Vol 236 ◽  
Author(s):  
Jeffrey S. Hale ◽  
R.A. Synowicki ◽  
S. Nafis ◽  
John A. Woollam
Keyword(s):  
Atomic Oxygen ◽  
Moisture Absorption ◽  
Crystalline Silicon ◽  
Carbon Films ◽  
Fused Silica ◽  
Low Earth Orbit ◽  
Index Of Refraction ◽  
Earth Orbit ◽  
Diamond Like Carbon ◽  
Space Flights

AbstractCVD deposited diamond-like carbon (DLC) films have been studied for possible use as a secondary standard for Low Earth Orbit materials degradation. Samples of various thicknesses have been exposed to a simulated Low Earth Orbit atomic oxygen (AO) environment using a plasma asher. Mass loss measurements indicate that DLC degrades at a rate of 0.7 mg/hr which is two to three times the rate of currently used Kapton samples which degrade at a rate of.3 mg/hr. Thickness measurements show that DLC thins at a rate of 77 Angstroms/min. Since DLC is not as susceptible to environmental factors such as moisture absorption, it could potentially provide more accurate measurements of AO fluence on short space flights. Adhesion of DLC films to both fused silica and crystalline silicon substrates has been studied under thermal cycling conditions. Film adhesion to fused silica can be enhanced by sputtering a thin layer of silicon dioxide onto the substrate prior to deposition. In addition to the above, the index of refraction and extinction coefficient of various thicknesses of DLC films has been characterized by Variable Angle Spectroscopic Ellipsometry.

Production Proven, High Precision Temporary Bond/De-bond Process

2013 ◽  
Vol 2013 (1) ◽  
pp. 000861-000865 ◽  
Author(s):  
Blake Dronen ◽  
Aric Shorey ◽  
B.K. Wang ◽  
Leon Tsai
Keyword(s):  
High Precision ◽  
Support System ◽  
Thickness Variation ◽  
Total Thickness ◽  
Critical Step ◽  
Low Coherence ◽  
Total Thickness Variation ◽  
Thinning Operations ◽  
Wafer Thinning

Wafer thinning represents a critical step in 2.5D and 3D-IC integration. Achieving low total thickness variation (TTV) of a bonded stack is essential since it directly impacts the TTV of the thinned device wafer. It is essential to understand and utilize appropriate processes and materials that provide precision bonded stacks prior to thinning operations in order to achieve high process yields. The 3M™ Wafer Support System and Corning's precision glass carrier wafers were used to produce bonded stacks. Leveraging metrology tools like the Flatmaster MSP-300 and low coherence interferometric probes allow for characterization of the TTV of each layer of a bonded stack and better understanding of the stack-up as well as how to minimize stack TTV. The ability to deliver stack TTV of < 2 um in a repeatable manner has been demonstrated.

Free Abrasive Machining in Slicing Brittle Materials With Wiresaw

2000 ◽  
Vol 123 (3) ◽  
pp. 254-259 ◽  
Author(s):  
Fuqian Yang ◽  
Imin Kao
Keyword(s):  
Process Parameters ◽  
Manufacturing Process ◽  
Brittle Materials ◽  
Stochastic Approach ◽  
Abrasive Machining ◽  
Photovoltaic Applications ◽  
Indentation Crack ◽  
Microelectronics Fabrication ◽  
The Relationship ◽  
Free Abrasive

Wiresaw has emerged as a leading technology in wafer preparation for microelectronics fabrication, especially in slicing large silicon wafers (diameter⩾300 mm) for both microelectronic and photovoltaic applications. Wiresaw has also been employed to slice other brittle materials such as alumina, quartz, glass, and ceramics. The manufacturing process of wiresaw is a free abrasive machining (FAM) process. Specifically, the wiresaw cuts brittle materials through the “rolling-indenting” and “scratch-indenting” processes where the materials removal is resulting from mechanical interactions between the substrate of the workpiece and loss abrasives, which are trapped between workpiece and wire. Built upon results of previous investigation in modeling of wiresaw, a model of wiresaw slicing is developed based on indentation crack as well as the influence of wire carrying the abrasives. This model is used to predict the relationship between the rate of material removal and the mechanical properties of the workpiece together with the process parameters. The rolling, indenting, and scratching modes of materials removal are considered with a simple stochastic approach. The model provides us with the basis for improving the efficiency of the wiresaw manufacturing process based on the process parameters.

Integration of CMP Fixed Abrasive Polishing into the Manufacturing of Thick Film SOI Substrates

2005 ◽  
Vol 867 ◽  
Author(s):  
Martin Kulawski ◽  
Hannu Luoto ◽  
Kimmo Henttinen ◽  
Tommi Suni ◽  
Frauke Weimar ◽  
...  
Keyword(s):  
Thick Film ◽  
Surface Damage ◽  
Silicon On Insulator ◽  
Thickness Variation ◽  
Process Sequence ◽  
Processing Times ◽  
Early Results ◽  
Total Thickness Variation ◽  
Soi Substrates ◽  
Fixed Abrasive

AbstractThe specification for the total thickness variation (TTV) of the device layers on thick-film silicon on insulator (SOI) wafers tighten for future applications. Therefore, the bulk removal polishing process of current technology after grinding cannot meet the demands in terms of flatness. The currently required amount of material removal for polishing out the induced sub surface damage (SSD) of the grinding is very high. Additionally, slurry-based CMP processes show unsatisfactory grindline and topography removal. This in turn reflects negatively to processing times, throughput and overall flatness performance.Encouraging early results of FA pad use for silicon and SOI polishing have already been further developed [1]. Low SSD grinding has been introduced to silicon manufacturing [[1]]. In this work, an integrated manufacturing process sequence is presented. Starting from low SSD grinding of the bonded SOI wafer couple, an optimized FA CMP step is replacing the conventional bulk polishing with reduced removal. The SSD after FA CMP is investigated by oxide induced stacking fault (OISF) method [[2]] and results are used to adjust the final polishing step of the substrates. The overall process sequence is highly advantageous in terms of performance in TTV and provides a highly competitive and effective method for achieving best possible surface quality with minimized total silicon removal. This method is not only useful for SOI wafers but also in other areas of silicon processing.

scholarly journals An Experimental Study on the Precision Abrasive Machining Process of Hard and Brittle Materials with Ultraviolet-Resin Bond Diamond Abrasive Tools

Materials ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 125 ◽  
Author(s):  
Lei Guo ◽  
Xinrong Zhang ◽  
Shibin Chen ◽  
Jizhuang Hui
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Manufacturing Process ◽  
Material Removal ◽  
Removal Rate ◽  
Machining Process ◽  
Abrasive Machining ◽  
Machining Performance ◽  
Machined Surface ◽  
Ultraviolet Curable

Ultraviolet-curable resin was introduced as a bonding agent into the fabrication process of precision abrasive machining tools in this study, aiming to deliver a rapid, flexible, economical, and environment-friendly additive manufacturing process to replace the hot press and sintering process with thermal-curable resin. A laboratory manufacturing process was established to develop an ultraviolet-curable resin bond diamond lapping plate, the machining performance of which on the ceramic workpiece was examined through a series of comparative experiments with slurry-based iron plate lapping. The machined surface roughness and weight loss of the workpieces were periodically recorded to evaluate the surface finish quality and the material removal rate. The promising results in terms of a 12% improvement in surface roughness and 25% reduction in material removal rate were obtained from the ultraviolet-curable resin plate-involved lapping process. A summarized hypothesis was drawn to describe the dynamically-balanced state of the hybrid precision abrasive machining process integrated both the two-body and three-body abrasion mode.

Development of Ultra-Precision Grinder for 300mm Wafers

2012 ◽  
Vol 565 ◽  
pp. 609-614 ◽  
Author(s):  
X.L. Zhu ◽  
Z.G. Dong ◽  
Ren Ke Kang ◽  
D.M. Guo
Keyword(s):  
Shape Control ◽  
State Of The Art ◽  
Surface Shape ◽  
Wafer Surface ◽  
Thickness Variation ◽  
Grinding Forces ◽  
Wafer Thickness ◽  
Ultra Precision ◽  
Total Thickness Variation ◽  
And Control

This study presents design of an ultra-precision wafer grinder which incorporates state-of-the-art automatic supervision and control system. The wafer grinder is characterized by wafer surface shape control, grinding forces and wafer thickness monitoring systems. The design provides a totally integrated solution to the ultra-precision grinder that is capable of grinding silicon wafers with surface roughness Ra<3 nm and total thickness variation<2µm/300mm.

A Novel Method to Modify the Lapping Uniformity for Silicon Wafer

2013 ◽  
Vol 562-565 ◽  
pp. 790-795
Author(s):  
Wen Jia Zuo ◽  
Xiao Hui Du ◽  
Hao Er Zhang ◽  
Yuan Zhe Su ◽  
Ting Ping Lei ◽  
...  
Keyword(s):  
Silicon Wafer ◽  
Removal Rate ◽  
Normal Pressure ◽  
Thickness Variation ◽  
Initial Stage ◽  
Equivalent Mass ◽  
Total Thickness Variation ◽  
Novel Method ◽  
Special Points ◽  
Stable Stage

In this paper, a novel lapping method based on regulating the position of carrier centroid is proposed to modify interfacial normal pressure uniformity. Eight special points are selected to represent carrier weight. This lapping process can be divided into initial stage, regulated stage and stable stage. The purpose of initial stage is calculating the position of carrier centroid according to the equivalent mass of eight points. The regulated stage is to decrease total thickness variation (TTV) by regulating the position of weight. Finally, the stable stage will keep uniformity of material removal rate (MRR) uniform at each point. A 3-inch and 400 μm thickness silicon wafer is lapped to demonstrate the feasibility of this method. We can find that TTV of this wafer decreases from initial stage 20 μm to 3 μm and remain constant. Therefore, the uniformity of MRR has been greatly improved by this novel lapping method.

Effect of Double Sided Process Parameters in Lapping Silicon Wafer

2013 ◽  
Vol 393 ◽  
pp. 259-265 ◽  
Author(s):  
Abdul Rahim Mahamad Sahab ◽  
Nor Hayati Saad ◽  
Amirul Abdul Rashid ◽  
Yusoff Noriah ◽  
Nassya Mohd Said ◽  
...  
Keyword(s):  
Silicon Wafer ◽  
Process Parameters ◽  
Integrated Circuit ◽  
Quality Standard ◽  
Wafer Surface ◽  
Thickness Variation ◽  
Total Thickness ◽  
Hard And Brittle Material ◽  
Total Thickness Variation ◽  
Lapping Machine

Silicon wafer is widely used in semiconductor industries for development of sensors and integrated circuit in computer, cell phones and wide variety of other devices. Demand on the device performance requires flatter wafer surface, and less dimensional wafer variation. Prime silicon wafer is hard and brittle material. Due to its properties, double sided lapping machine with ceramic grinding agent were introduced for machining high quality standard silicon wafers. The main focus is the silicon wafer with high accuracy of flatness; to reduce total thickness variation, waviness and roughness. In this paper the lapping experiment and analysis showed that the double sided lapping machine is able to produce total thickness variation less than 10 um at controlled process parameters within short processing time. Machining using low mode method reduced the total thickness variation (TTV) value. The lapping load and speed directly reflected the performance and condition of final silicon wafer quality.

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