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Electrical Wetting Phenomena

Electrical Wetting Phenomena

The electrowetting effect has been defined as “the change in solid-electrolyte contact angle due to an applied potential difference between the solid and the electrolyte”. The phenomenon of electrowetting can be understood in terms of the forces that result from the applied electric field.  It is also known that the contact angle supression or saturation phenomenum through voltage can be affected by changing the detailed geometry of the system.  It is predicted that  in reversed electrowetting, the contact angle can possibly grow with the voltage.

Electrowetting is now used in a wide range of applications from modular to adjustable lenses, electronic displays (e-paper) as well as switches for optical fibers. Electrowetting has recently been evoked for manipulating Soft Matter.  Furthermore, filters with electrowetting functionality has been suggested for cleaning oil spills and separating oil-water mixtures.  By optically modulating the number of carriers in space-charge region of the semiconductor, the contact angle of a liquid droplet can be altered in a continuous way.  This is called photoelectricalwetting and it can be observed if the conductor in the liquid/insulator/conductor stack used for electrowetting is replaced by a semionductor.

Our devices which can help you: OCA15, OCA20, OCA25, OCA35, OCA50, TEC, EFC, PMC, HGC, Electro-wetting platform EWP100, etc. 


Surface Structures Fabrication and Verification

Surface Structures Fabrication and Verification

A fine (micro- or nano-patterned) Si-based mold is fabricated by a conventional VLSI process and the mold is directly pressed to a thin glass plate using a hot-press machine.  Fabrication of fine grating on a glass surface can be achieved by imprint lithography using a Si3N4/SiO2/Si mold and a low Tg glass. The imprint conditions are designed based on the glass surface property measured under a temperature, humidity or pressure controlled condition.  Recently micro-fluidics research will rely on the similar imprint and etching processes to create the desired patterns or channel designs as another example in other modern applications.

FDS/Dataphysics can help in the steps  of  your VLSI processes 

Lithography is used to transfer a pattern from a photomask to the surface of the wafer. The photoresistant coverage and wetting nature on the wafer surface will determine the effectiveness of the partner trafer when exposed to (often ultraviolet) light or another source of illumination (e.g. X-ray).  Therefore, the surface preparation of the wafer and selection of photoresistant needs to be checked with a contact angle meter OCA and tensiometer such as DCAT, t15, t100, etc.

Etching is used to remove material selectively in order to create patterns.   The selectivity and completeness of the etching are always desired by the process engineers and they can be verified with a contact angle device, OCA.

Deposition- A multitude of layers of different materials have to be deposited during the IC fabrication process. The two most important deposition methods are the physical vapor deposition (PVD) and the chemical vapor deposition (CVD). During PVD accelerated gas ions sputter particles from a sputter target in a low pressure plasma chamber. The principle of CVD is a chemical reaction of a gas mixture on the substrate surface at high temperatures. The need of high temperatures is the most restricting factor for applying CVD. This problem can be avoided with plasma enhanced chemical vapor deposition (PECVD), where the chemical reaction is enhanced with radio frequencies instead of high temperatures. An important aspect for this technique is the uniformity of the deposited material, especially the layer thickness.  You can use an OCA device to check on the uniformity of the deposited material.

Chemical Mechanical Planarization– Processes like etching, deposition, or oxidation, which modify the topography of the wafer surface lead to a non-planar surface. Chemical mechanical planarization (CMP) is used to plane the wafer surface with the help of a chemical slurry. First, a planar surface is necessary for lithography due to a correct pattern transfer.  The CMP slurry formulations can be optimized with a DCAT tensiometer or a MutiScan and the planarity of the wafer after CMP can be examined with a fully automated OCA50 contact angle scanning and mapping features.

Oxidation is a process which converts silicon on the wafer into silicon dioxide. The chemical reaction of silicon and oxygen already starts at room temperature but stops after a very thin native oxide film. For an effective oxidation rate the wafer must be settled to a furnace with oxygen or water vapor at elevated temperatures. Silicon dioxide layers are used as high-quality insulators or masks for ion implantation. The quality of the formed silicon dioxide can be examined with an OCA25 equipped with a temperature, humidity or pressure chamber.

Ion implantation is the dominant technique to introduce dopant impurities into crystalline silicon. This is performed with an electric field which accelerates the ionized atoms or molecules so that these particles penetrate into the target material until they come to rest because of interactions with the silicon atoms. Ion implantation is able to control exactly the distribution and dose of the dopants in silicon, because the penetration depth depends on the kinetic energy of the ions which is proportional to the electric field.  With an OCA25 and one of environmental chamber for either electrical field, pressure, temperature or humidity, you can research for an optimized ion implantation process.

Enhanced Oil Recovery/Oil Drilling/Petroleum Geology

Enhanced Oil Recovery/Oil Drilling/Petroleum Geology

Enhanced Oil Recovery (EOR) technologies are used to increase the amount of oil that can be extracted from an existing oil field after the primary and secondary production stages. These technologies play on the physics of how oil is trapped in the rocks and are primarily aimed at either decreasing the interfacial forces holding the oil in pores within the rock formation, reducing the viscosity difference between the oil and water phases, or modifying the reservoir and oil properties to release the oil more easily.

With increasing global energy demand, high-sustained oil prices, aging oil fields and a scarcity of conventional oil discovery, enhanced oil recovery techniques are set to play an increasingly important role in the global oil industry over the coming decades.  Although some short-term downturns occurred through the years, the growth rates and EOR methods employed vary considerably from country to county; a strong growth in oil recovery is still anticipated in each of the three main EOR sub-markets: thermal, gas and chemical.

Application scope for EOR:

-Identify commercially available additives, which are effective in reducing the mobility of carbon dioxide (CO2), thereby improving its efficiency and yield in the recovery of tertiary oil

-The control and/or  reduction in oil saturation  with a waterflood-containing surfactant concentration

-The use of foam to lower the mobility of gases used to displace oil

-Visco-elasticity measurements at varying shear help explain the dramatic change in gas/liquid/oil mobility

-Selection of the added surfactants and water-soluble polymers

-Environmental remedy and protection issues


Our devices which can help: OCA, DCAT, SVT20, ODG25, T100, T15+, etc.

On-line Surface/Auto Parts/Metal Cleaning

On-line Surface/Auto Parts/Metal Cleaning

For massive part production quantity, and associated surface finishing industries, the name of the game in today’s competitive landscape is speed combined with consistent quality and robustness.  The ‘speed’ refers to time-to-market and how early developers can create superior offers to their customers.  Any later entrants, are competitors to this first application in market place as consistent challengers. What should they do to get market advantages?

Company failures in supplying consistent parts to satisfy their customers in very competitive and thin-profit markets can cost them their reputation and decrease business success. Therefore, massive manufacturers of original and duplicate parts face economic pressure as they cannot afford manual production and testing resources, while there is an imminent need to reduce the overall handling costs.  This scratches the surface in explaining why the automation actually saves you money, time and resources – when an on-line cleaning and testing process is implemented and adopted efficiently.

An automated on-line cleanliness testing capability provides various benefits to auto/metal parts makers; coverage to detect defects and errors immediately and significantly reduces the cost of failure, saves time through its repeatability and early verification, and leverages the improved resource productivity.

Our devices which can help in your on-line cleanliness testing are: SITA CleanLine ST, SITA CleanLine Cl, SITA Cleanline ConSpector, SITA In-Line, Dataphysics PCA100 and etc.

Food and Flavor Formulations

Food and Flavor Formulations

Food texture is one of the major criteria that consumers use to judge the quality and freshness of consumables. When a food produces a physical sensation in the mouth (hard, soft, crispy, moist, dry, etc.), the consumer has a basis for determining the food’s quality (fresh, stale, tender, ripe).  A major challenge facing food developers is how to accurately and objectively measure texture and mouth feel. Texture is a composite property related to a number of physical properties (e.g., viscosity and elasticity), and the relationship is complex.  Mouth feel is difficult to define. It involves a food’s entire physical and chemical interaction in the mouth.  Therefore, it refers to a complex sensory attribute encompassing feeling and trigeminal impulses of texture, heat, coolness, sponginess, lubricity, sliminess, chalkiness, fullness, crispness, flavor, etc.

With the selected ingredients, additives, and flavors in correlation with newly available processing procedures and technologies, food formulators can magically create mouth feels in food products to represent very appealing level of the following characteristics: cohesiveness, density(compactness), dryness, fracturability (crispiness, crunchiness and brittleness), graininess, gumminess, hardness, heaviness, moisture absorption, moisture release, mouth coating, roughness, abrasiveness, slipperiness, smoothness, uniformity(homogeneity), uniformity of bite, uniformity of chew, viscosity, wetness, springiness. etc.

The challenge confronting food designers who want to quantify mouth-feel characteristics using an instrumental technique: How to take instrument readings — measurements of forces, distances, stability, shelf-life, wetting angle, surface energy and surface tension that look like numbers from a physics experiment– and relate them to something meaningful and relevant to what people actually experience when they taste, chew or drink.  FDS/SITA/Dataphysics’ application experts can help you with their experiences.

Our precision devices which can help you overcome the challenge are: DCATs, OCAs, RN4.2, LK2.2, T100, T15+, Dynotester, ODG25, SVT20, DCAT-LBE, and many QC tools for hardness, water penetration, tearing strength, freezing test, etc.