Abstract: Methods and devices including an air gap adjacent a contact element extending to a source/drain feature of a device are described. Some embodiments of the method include depositing a dummy layer, which is subsequently removed to form the air gap. The dummy layer and subsequent air gap may be formed after a SAC dielectric layer such as silicon nitride is formed over an adjacent metal gate structure.

Abstract: Epitaxial source/drain structures for enhancing performance of multigate devices, such as fin-like field-effect transistors (FETs) or gate-all-around (GAA) FETs, and methods of fabricating the epitaxial source/drain structures, are disclosed herein. An exemplary device includes a dielectric substrate. The device further includes a channel layer, a gate disposed over the channel layer, and an epitaxial source/drain structure disposed adjacent to the channel layer. The channel layer, the gate, and the epitaxial source/drain structure are disposed over the dielectric substrate. The epitaxial source/drain structure includes an inner portion having a first dopant concentration and an outer portion having a second dopant concentration that is less than the first dopant concentration. The inner portion physically contacts the dielectric substrate, and the outer portion is disposed between the inner portion and the channel layer. In some embodiments, the outer portion physically contacts the dielectric substrate.

Abstract: A device includes a gate stack; a gate spacer on a sidewall of the gate stack; a source/drain region adjacent the gate stack; a silicide; and a source/drain contact electrically connected to the source/drain region through the silicide. The silicide includes a conformal first portion in the source/drain region, the conformal first portion comprising a metal and silicon; and a conformal second portion over the conformal first portion, the conformal second portion further disposed on a sidewall of the gate spacer, the conformal second portion comprising the metal, silicon, and nitrogen.

Abstract: In an embodiment, a device includes: a gate electrode; a epitaxial source/drain region adjacent the gate electrode; one or more inter-layer dielectric (ILD) layers over the epitaxial source/drain region; a first source/drain contact extending through the ILD layers, the first source/drain contact connected to the epitaxial source/drain region; a contact spacer surrounding the first source/drain contact; and a void disposed between the contact spacer and the ILD layers.

Abstract: A hydrophobic admixture, for cementitious materials such as cement paste, mortar, and concrete, includes solid polymer particles with a coating of hydrophobic agent and surfactant. The solid polymer particles adhere to exterior surfaces of hydrated cement particles in the cement matrix. The solid polymer particles deliver the hydrophobic agent into the cement matrix which is hydrophilic. The hydrophobic agents are distributed uniformly throughout the cement matrix. The solid polymer particles can be crumb rubber particles derived from waste rubber tires, recycled plastics and similar solid materials. The hydrophobic liquid agent is derived from waste lubricant oil, spent motor oil, base oil, esters of fatty acids, vegetable oil and the like. Fine particles such as activated carbon, silica fume and spent catalyst can be employed to fill the large pores or cracks that develop in the cementitious matrix. The cured cementitious materials exhibit high contact angles and high compressive strengths.

Abstract: A hydrophobic admixture, for cementitious materials such as cement paste, mortar, and concrete, includes solid polymer particles with a coating of hydrophobic agent and surfactant. The solid polymer particles adhere to exterior surfaces of hydrated cement particles in the cement matrix. The solid polymer particles deliver the hydrophobic agent into the cement matrix which is hydrophilic. The hydrophobic agents are distributed uniformly throughout the cement matrix. The solid polymer particles can be crumb rubber particles derived from waste rubber tires, recycled plastics and similar solid materials. The hydrophobic liquid agent is derived from waste lubricant oil, spent motor oil, base oil, esters of fatty acids, vegetable oil and the like. Fine particles such as activated carbon, silica fume and spent catalyst can be employed to fill the large pores or cracks that develop in the cementitious matrix. The cured cementitious materials exhibit high contact angles and high compressive strengths.

Abstract: A hydrophobic admixture, for cementitious materials such as cement paste, mortar, and concrete, includes solid polymer particles with a coating of hydrophobic agent and surfactant. The solid polymer particles adhere to exterior surfaces of hydrated cement particles in the cement matrix. The solid polymer particles deliver the hydrophobic agent into the cement matrix which is hydrophilic. The hydrophobic agents are distributed uniformly throughout the cement matrix. The solid polymer particles can be crumb rubber particles derived from waste rubber tires, recycled plastics and similar solid materials. The hydrophobic liquid agent is derived from waste lubricant oil, spent motor oil, base oil, esters of fatty acids, vegetable oil and the like. Fine particles such as activated carbon, silica fume and spent catalyst can be employed to fill the large pores or cracks that develop in the cementitious matrix. The cured cementitious materials exhibit high contact angles and high compressive strengths.

Abstract: Recovering a polar hydrocarbon (HC) selective solvent substantially free of hydrocarbons (HCs) and other impurities from a lean solvent stream containing the selective solvent, measurable amounts of heavy aromatic HCs, and polymeric materials that are generated in an extractive distillation (ED) or liquid-liquid extraction (LLE) process. At least a portion of the lean solvent stream is contact in a solvent clean-up zone with a slip stream from the HC feed stream of the ED or LLE process or an external stream. The HC feed stream, such as pyrolysis gasoline or reformate, contains significant amounts of benzene and at least 50% polar (aromatic) HCs and serves as a displacement agent to remove the heavy HCs and polymeric material from the lean solvent stream. A magnetic filter can be used to remove the paramagnetic contaminants from the lean solvent.

Abstract: A high capacity magnetic filter separates diamagnetic and/or paramagnetic substances from fluid streams. Diamagnetic solid substances are magnetized under an external magnetic field through coordinated interaction of diamagnetic solid substances with an inducement paramagnetic material (IPM). The magnetic filter serves as a separation zone created by the presence of IPM and magnets that are shielded from the IPM by non-magnetic sleeves or partitions. The IPM in the void volume between the magnets affords large surface area onto which diamagnetic and paramagnetic materials can contact and be attracted to. The relative position and distance of the magnetic source, such a magnetic bar or electromagnet, to the solid mixture of diamagnetic and IPM are adjusted to induce sufficiently strong magnetism in the diamagnetic solids which causes the diamagnetic solids to be attracted by the magnetic field as well. Both diamagnetic and paramagnetic substances can be removed from a liquid or gas.

Abstract: Extractive distillation for recovering aromatic hydrocarbons employs an extractive distillation column with a novel overhead system including a partial condenser. The process enables (i) efficient removal of heavy non-aromatics, particularly C8 naphthenic compounds, from the EDC bottom stream to increase the purity of aromatic products, especially of the mixed xylenes and (ii) reduction (or better control) of benzene loss to the raffinate product stream to maintain its quality as a gasoline blend stock and, as a result, enhance benzene recovery in the aromatic products. Feedstock includes a full-range feedstock, such as pyrolysis gasoline, or a narrow-range feedstock, such as reformate.

Abstract: A novel design of filters for removing iron rust particulates and other polymeric sludge from refinery and chemical process streams that are paramagnetic in nature is provided. The performance of these filters is greatly enhanced by the presence of the magnetic field induced by magnets. Basically, the filter comprises a high-pressure vessel with means to support the plurality of magnets in the form of bars or plates that are encased in stainless steel tubes or columns. Filters with various configurations are disclosed for accommodating the removal of contaminants from the process streams of different industries, with high efficiency for contaminants removal, simple construction, low operational and maintenance costs, and low hazardous operation.

Abstract: Recovering high purity benzene from hydrocarbon feedstock containing aromatics and non-aromatics is implemented by simple and low-cost modifications to conventional extractive distillation columns (EDCs). Methyl cyclohexane (MCH) that is generated through non-selective hydrogenation of toluene in hydrodesulfurization (HDS) units is a major contaminant in benzene production. To meet MCH specifications, often times the extractive distillation (ED) process for recovering purified benzene is operated with excessive benzene loss to the overhead raffinate stream, producing a lower quality non-aromatic product.

Abstract: A magnetic filter employs a magnetic core assembly that incorporates a plurality of exchangeable holder sleeves, each enclosing permanent magnets. Neither the sleeves nor magnetic bars are mechanically fixed to the filter housing. The magnet bars and holder sleeves are individually accessible. The number of holder sleeves in the magnetic core assembly is flexible. The magnetic filter in equipped with a screen that partially encloses the elongated holder sleeves to treat streams that contain degradation sludge, iron containing particles or flakes, and non-magnetic polymeric materials. In operation, a feed stream initially contacts the magnetic core assembly where paramagnetic contaminants become deposited onto the exterior surface of the holder sleeves under direct influence of strong magnetic field generated by the magnet bars. The mesh screen cylinder subsequently captures non-magnetic and weakly magnetic contaminants of a certain size before the cleaned stream exits the magnetic filter.

Abstract: Deasphalted residual oil (DAO) and the aromatics-rich extract that is derived from DAO have low polycyclic aromatics contents, relatively low aniline points, and high flash points. They form blending stocks that improve properties of mixed feedstocks to consistently produce environmentally qualified rubber processing oil (RPO) by extraction under low solvent-to-oil ratios and moderate extraction temperatures. Distilling a petroleum crude oil under atmospheric pressure generates a bottom residual oil which is then subject to vacuum distillation to yield a bottom residual oil. DAO is produced by removing the asphalt from the vacuum bottom residual oil through extraction with light paraffinic solvent. The extract of DAO is a co-product in the production of the bright stock of the lubricating oil through extraction. The feedstock is mixed with the extract from a petroleum fraction boiling in lube oil range.

Abstract: A method for cross connecting the lean solvent supply lines between the liquid liquid extraction (LLE) and the extractive distillation (ED) processes thereby using the LLE column as the outlet for removing accumulated heavy hydrocarbons (HCs) and polymeric materials from the solvent loop of both processes to maintain their solvent performance. The unique capabilities of the LLE column in rejecting heavy HCs from the solvent into a raffinate product stream that leaves the system enable the removal of the accumulated heavy HCs and polymeric materials from the closed solvent loop of the ED process when their lean solvent loop are cross connected. Cross connection requires minimum equipment change. In the revamped system, the solvent recovery column (SRC) in LLE process supplies lean solvent for the extractive distillation column while the SRC of the ED process supplies lean solvent for LLE column.

Abstract: Solvent regeneration to recover a polar hydrocarbon (HC) selective solvent substantially free of hydrocarbons (HCs) and other impurities from a solvent-rich stream containing selective solvent, heavy HCs, and polymeric materials (PMs) generated from reactions among thermally decomposed or oxidized solvent, heavy HCs, and additives is provided. A combination of displacement agent and associated co-displacement agent squeezes out the heavy HCs and PMs from the extractive solvent within a solvent clean-up zone. Simultaneously, a filter equipped with a magnetic field is positioned in a lean solvent circulation line to remove paramagnetic contaminants. The presence of the co-displacement agent significantly enhances the capability of the displacement agent in removing the heavy HCs and PMs from the extractive solvent.

Abstract: A two-stage sealed magnetic filter continuously removes magnetic and non-magnetic contaminants from liquid process streams. Elongated non-magnetic holder sleeves encasing magnet bars attract magnetic contaminants while a screen cylinder captures non-magnetic contaminants. The magnet bars are accessible without having to open the interior of the housing to the environment. Thus, during maintenance, removing the magnet bars from the holder sleeves releases the magnetic contaminants that have adhered to the holder sleeves into the screen cylinder which partially encloses the holder sleeves. Contaminants are flushed out of the magnetic filter without exposing workers to potentially hazardous substances. Polymeric sludge occluded with iron compounds can be effectively removed from streams in refineries and chemical plants. The iron compounds are formed from carbon steel which is prevalent in plant machinery and that corrodes in the presence of acidic contaminants.

Abstract: Non-basic and non-acidic homogeneous catalysts organo-metallic compound of the formula: M(OCH3)x wherein M is B, Na, Mg, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Al, Sn, Sb, Mo, Ag, and Cd and x is an integer from 2, 3 or 4 can catalyze transesterification of oils and fats having high free fatty acid content and with an acid number from 0.5 to 20, into biodiesel. B(OCH3)3 and Ge(OCH3)4, having low boiling points, are easily recovered from the biodiesel and glycerol phases and recycled for reuse. Continuous biodiesel production with the novel homogenous catalysts is achieved without the complicated and troublesome steps attendant with conventional processes using base or acid homogeneous catalyst. The high purity biodiesel is produced without acid-base neutralization, water wash, filtration, and solid disposal steps for removing the spent catalyst from the product streams associated with prior techniques.

Abstract: A magnetic filter employs a magnetic core assembly that incorporates a plurality of exchangeable holder sleeves, each enclosing permanent magnets. Neither the sleeves nor magnetic bars are mechanically fixed to the filter housing. The magnet bars and holder sleeves are individually accessible. The number of holder sleeves in the magnetic core assembly is flexible. The magnetic filter in equipped with a screen that partially encloses the elongated holder sleeves to treat streams that contain degradation sludge, iron containing particles or flakes, and non-magnetic polymeric materials. In operation, a feed stream initially contacts the magnetic core assembly where paramagnetic contaminants become deposited onto the exterior surface of the holder sleeves under direct influence of strong magnetic field generated by the magnet bars. The mesh screen cylinder subsequently captures non-magnetic and weakly magnetic contaminants of a certain size before the cleaned stream exits the magnetic filter.

Abstract: Solvent regeneration to recover a polar hydrocarbon (HC) selective solvent substantially free of hydrocarbons (HCs) and other impurities from a solvent-rich stream containing selective solvent, heavy HCs, and polymeric materials (PMs) generated from reactions among thermally decomposed or oxidized solvent, heavy HCs, and additives is provided. A combination of displacement agent and associated co-displacement agent squeezes out the heavy HCs and PMs from the extractive solvent within a solvent clean-up zone. Simultaneously, a filter equipped with a magnetic field is positioned in a lean solvent circulation line to remove paramagnetic contaminants. The presence of the co-displacement agent significantly enhances the capability of the displacement agent in removing the heavy HCs and PMs from the extractive solvent.