The present invention relates to curing of semiconductor wafers. More particularly, the invention relates to cure chambers containing multiple cure stations, each featuring one or more UV light sources. The wafers are cured by sequential exposure to the light sources in each station. In some embodiments, the wafers remain stationary with respect to the light source during exposure. In other embodiments, there is relative movement between the light source and the wafer during exposure. The invention also provides chambers that may be used to independently modulate the cross-linking, density and increase in stress of a cured material by providing independent control of the wafer temperature and UV intensity.

Single-chamber sequential curing of semiconductor wafers

A substrate processing method includes a liquid processing process that supplies a processing liquid onto a substrate to process the substrate; a heating process that heats the substrate on which a liquid film of the processing liquid is formed; a supplying process that supplies a volatile processing liquid to the substrate on which the liquid film of the processing liquid is formed; a stopping process that stops the supply of the volatile processing liquid to the substrate; and a drying process that dries the substrate by removing the volatile processing liquid, in which the heating process starts before the supplying process that supplies the volatile processing liquid and the substrate is heated so that the surface temperature of the substrate is higher than a dew point before the surface of the substrate is exposed from the volatile processing liquid.

Substrate processing method and substrate processing apparatus

A method of manufacturing a miniature electromechanical system (MEMS) device includes the steps of forming a moving member on a first substrate such that a first sacrificial layer is disposed between the moving member and the substrate, encapsulating the moving member, including the first sacrificial layer, with a second sacrificial layer, coating the encapsulating second sacrificial layer with a first film formed of a material that establishes an hermetic seal with the substrate, and removing the first and second sacrificial layers.

Thin film encapsulation of mems devices

Disclosed are methods for fabricating encapsulated microelectromechanical systems (MEMS) devices. A MEMS device fabricated on a CMOS wafer is encapsulated using an etch resistant thin film layer prior to the release of the MEMS device. Once CMOS processing is completed, the wafer is etched to release the MEMS device. If the MEMS is fabricated on a silicon-on-insulator (SOI) wafer, the buried oxide of the SOI wafer acts as an etch stop for the etching. A sacrificial layer(s) is accessed and removed from the back side of the wafer, while the front side of the wafer is protected by a masking layer. The MEMS device is released without having any detrimental effects on CMOS components. If desired, the wafer can be mounted on another substrate to provide hermetic or semi-hermetic sealing of the device.

Method for sealing and backside releasing of microelectromechanical systems

Disclosed are moveable microstructures comprising in-plane capacitive microaccelerometers, with submicro-gravity resolution ( 17 pF/g). The microstructures are fabricated in thick (>100 μm) silicon-on-insulator (SOI) substrates or silicon substrates using a two-mask fully-dry release process that provides large seismic mass (>10 milli-g), reduced capacitive gaps, and reduced in-plane stiffness. Fabricated devices may be interfaced to a high resolution switched-capacitor CMOS IC that eliminates the need for area-consuming reference capacitors. The measured sensitivity is 83 mV/mg (17 pF/g) and the output noise floor is −91 dBm/Hz at 10 Hz (corresponding to an acceleration resolution of 170 ng/√Hz). The IC consumes 6 mW power and measures 0.65 mm 2 core area.

Capacitive microaccelerometers and fabrication methods

An apparatus and process for treating at least a portion of the surface of a substrate is described herein. In one aspect, the apparatus a processing chamber comprising an inner volume, the substrate, and an exhaust manifold; an activated reactive gas supply source wherein a process gas comprising one or more reactive gases and optionally an additive gas is activated by one or more energy sources to provide the activated reactive gas; and a distribution conduit, which is in fluid communication with the inner volume and the supply source, comprising: a plurality of openings that direct the activated reactive gas into the inner volume, wherein the activated reactive gas contacts the surface and provides a spent activated reactive gas and/or volatile products that are withdrawn from the inner volume through the exhaust manifold.

Apparatus and process for surface treatment of substrate using an activated reactive gas

A method for removing sacrificial materials and metal contamination from silicon surfaces during the manufacturing of an integrated micromechanical device and a microelectronic device on a single chip is provided which includes the steps of adjusting the temperature of the chip using a reaction chamber to a temperature appropriate for the selection of a beta-diketone and the design of micromechanical and microelectronic devices, cycle purging the chamber using an inert gas to remove atmospheric gases and trace amounts of water, introducing HF and the beta-diketone as a reactive mixture into the reaction chamber which contains at least one substrate to be etched, flowing the reactive mixture over the substrate until the sacrificial materials and metal contamination have been substantially removed, stopping the flow of the reactive mixture; and cycle purging the chamber to remove residual reactive mixture and any remaining reaction by-products. Optionally, an oxidant gas may be added to the reactive mixture to promote the oxidation of metal species.

Method to remove metal and silicon oxide during gas-phase sacrificial oxide etch

Several strategies were employed to improve the transparency and etch resistance of the acrylate-based 157 nm photoresists. (1) α-Fluorinated acrylates were synthesized and polymerized using radical initiation. The homopolymer of 2-[4-(2-hydroxy-hexafluoroisopropyl)cyclohexane]hexafluoro isopropyl-α-monofluoroacrylate (FA) showed high transparency at 157 nm (A = 1.7 μm-1), and its copolymer with norbornene hexafluoroalcohol and α-fluoro-tert-butylacrylate shows good 248 nm lithographic performance. (2) Selected acrylates containing hexafluoroisopropyl groups and hydrogenated single ring and multi-ring systems were prepared to address etch resistance. Homopolymers of acrylic versions of FA with different alicyclic moieties such as 1,3-cyclohexane, hydrogenated diphenyl ether and decaline showed very good transparency at 157 nm (A = 1.8 μm-1, 2.4 μm-1, 2.6 μm-1, respectively). Tg values for these homopolymers were determined to be in the range of 91-95°C. (3) The POSS group was also used to improve etch resistance. POSS-containing non-fluorinated acrylate copolymers showed absorbances of 3.0-3.3 μm-1 at 157 nm. POSS containing α-trifluoromethylacrylate polymers are expected to have lower absorbance. (4) To utilize an alternating copolymerization scheme, new fluorinated monomers containing both electron-rich and electron-deficient double bonds in one molecule were synthesized. The monomers were designed to undergo cyclopolymerization to generate polymers for improved transparency, etch resistance and outgassing properties.

Strategies for High Transparency Acrylate Resists for 157 nm Lithography

Photolithography using the F2 excimer laser at 157 nm, a technology to bridge traditional optical lithography and next generation lithographies, promises to enable ultralarge scale integrated devices with sub-70 nm design rules. Chemically amplified resists based on fluoropolymers have previously been shown to be good candidates for 157 nm microlithography. In our research, hexafluoroisopropyl alcohol (HFIPA) groups have been incorporated into polymers to improve the base solubility and to increase the transparency needed for new photoresists at 157 nm. These new polymers have absorbance values at 157 nm ranging from 1.7 to 3.9 μm−1. The introduction of fluorine groups increases their hydrophobicity and makes these polymers more difficult to wet at the surface. We have studied the effect of fluorine content on hydrophobicity of fluorinated polymers by measuring contact angle data over short time intervals. The ability to combine fluoropolymer synthesis with extensive contact angle studies has proven to be...

Wetting and dissolution studies of fluoropolymers used in 157 nm photolithography applications

Electromagnetic radiation in the vacuum-ultraviolet (VUV) region is needed for imaging of very fine features at the 65 nm and 45 nm nodes. Photolithography using 157-nm radiation, emitted from an F 2 excimer laser, is a candidate for next generation lithography. Only chemically amplified resists containing fluorinated hydrocarbons and siloxanes have the required transparency at this wavelength. We have identified hexafluoroisopropanol units as a building block for our 157-nm resist polymers. This paper reports our progress on the most recent research development for this platform. The hexafluoroisopropanol functionality, which has a pKa similar to phenol, has been used to increase the transparency of 157-nm single-layer acrylate-based resists. Our recent effort has been focused on the syntheses of new acrylate monomers with highly transparent building blocks based on trifluoroacetone. The first example, a homopolymer derived from trifluoroacetone bearing a fluorinated hemiacetal unit, has moderate transparency at 157 nm (A = 1.9 μm -1 ). We have also introduced a new acrylate monomer containing a trimer based on trifluoroacetone, where the 6-hydroxy group in the hemiacetal unit is substituted by a fluorine atom, with an acceptable transparency at 157 nm (A = 2.1 μm -1 ). Copolymers of the former monomer, derived from trifluoroacetone, and tert -butyl α-fluoroacrylate have also been prepared and showed good 248-nm lithographic performance suggesting suitability for 157-nm lithography. This paper will discuss the transparency, etch resistance and chemical properties of several fluorinated acrylate-based resists, synthesized from groups containing pendent hexafluoroisopropanol units and trimers derived from trifluoroacetone.

Eric Anthony Robertson

Papers

Apparatus and process for surface treatment of substrate using an activated reactive gas

Method to remove metal and silicon oxide during gas-phase sacrificial oxide etch

Strategies for High Transparency Acrylate Resists for 157 nm Lithography

Wetting and dissolution studies of fluoropolymers used in 157 nm photolithography applications

Hexafluoroisopropyl and trifluoromethyl carbinols in an acrylate platform for 157-nm chemically amplified resists