Abstract:
A semiconductor accelerometer is formed by attaching a semiconductor layer to a handle wafer by a thick oxide layer. Accelerometer geometry is patterned in the semiconductor layer, which is then used as a mask to etch out a cavity in the underlying thick oxide. The mask may include one or more apertures, so that a mass region will have corresponding apertures to the underlying oxide layer. The structure resulting from an oxide etch has the intended accelerometer geometry of a large volume mass region supported in cantilever fashion by a plurality of piezo-resistive arm regions to a surrounding, supporting portion of the semiconductor layer. Directly beneath this accelerometer geometry is a flex-accommodating cavity realized by the removal of the underlying oxide layer. The semiconductor layer remains attached to the handle wafer by means of the thick oxide layer that surrounds the accelerometer geometry, and which was adequately masked by the surrounding portion of the top semiconductor layer during the oxide etch step. In a second embodiment support arm regions are dimensioned separately from the mass region, using a plurality of buried oxide regions as semiconductor etch stops.
Abstract:
A laminated structure includes a wafer member with a membrane attached thereto, the membrane being formed of substantially hydrogen-free boron nitride having a nominal composition B.sub.3 N. The structure may be a component in a mechanical device for effecting a mechanical function, or the membrane may form a masking layer on the wafer. The structure includes a body formed of at least two wafer members laminated together with a cavity formed therebetween, with the boron nitride membrane extending into the cavity so as to provide the structural component such as a support for a heating element or a membrane in a gas valve. In another aspect borom is selectively diffused from the boron nitride into a surface of a silicon wafer. The surface is then exposed to EDP etchant to which the diffusion layer is resistant, thereby forming a channel the wafer member with smooth walls for fluid flow.
Abstract:
The invention concerns, in particular, a method for producing patterns in a layer to be etched (410), from a stack comprising at least the layer to be etched (410) and one masking layer (420) overlying the layer to be etched (410), the masking layer (420) having at least one pattern (421), the method comprising at least: a) a step of modifying at least one area (411) of the layer to be etched (410) by ion implantation (430) in line with the at least one pattern (421); b) at least one sequence of steps comprising: b1) a step (440) of enlarging the at least one pattern (421) in a plane in which the layer (410) to be etched mainly extends; b2) a step of modifying at least one area (411', 411'') of the layer to be etched (410) by ion implantation (430) in line with the at least one enlarged pattern (421), the implantation being carried out at a depth less than the implantation depth of the preceding modification step; c) a step (461, 462) of removing the modified areas (411, 411', 411''), the removal comprising a step of etching the modified areas (411, 411', 411'') selectively to the non-modified areas (412) of the layer (410) to be etched.
Abstract:
The invention relates, in particular, to a method for producing subsequent patterns in an underlying layer (120), the method comprising at least a step of producing previous patterns in a printable layer (110) overlying the underlying layer (120), the production of the previous patterns comprising the nanoimprinting of the printable layer (110) and leaving in place a continuous layer formed by the printable layer (110) and covering the underlying layer (120), characterised in that it comprises the following step: at least one step of modifying the underlying layer (120) by ion implantation (421) in the underlying layer (120), the implantation (421) being carried out through the printable layer (110) comprising the subsequent patterns, the implantation (421) parameters being chosen so as to form, in the underlying layer (120), implanted areas (122) and non-implanted areas, the non-implanted areas defining the subsequent patterns and having a geometry that is dependent on the previous patterns.
Abstract:
A wafer for use in a MEMS device having two doped layers surrounding an undoped layer of silicon is described. By providing two doped layers around an undoped core, the stress in the lattice structure of the silicon is reduced as compared to a solidly doped layer. Thus, problems associated with warping and bowing are reduced. The wafer may have a pattered oxide layer to pattern the deep reactive ion etch. A first deep reactive ion etch creates trenches in the layers. The walls of the trenches are doped with boron atoms. A second deep reactive ion etch removes the bottom walls of the trenches. The wafer is separated from the silicon substrate and bonded to at least one glass wafer.
Abstract:
Die Erfindung beschreibt ein Herstellungsverfahrens eines insbesondere mikromechanischen Halbleiterbauelements sowie ein mit diesem Verfahren hergestelltes Halbleiterbauelement. Zur Herstellung des Halbleiterbauelements ist vorgesehen, dass auf einem Halbleiterträger ein strukturiertes Stabilisierungselement mit wenigstens einer Öffnung erzeugt wird. Die Öffnung ist dabei so angebracht, dass sie den Zugang zu einem mit einer ersten Dotierung aufweisenden ersten Bereich im Halbleiterträger erlaubt. Weiterhin ist ein selektives Herauslösen wenigstens eines Teils des mit der ersten Dotierung versehenen Halbleitermaterials aus dem ersten Bereich des Halbleiterträger vorgesehen. Darüber hinaus wird mittels einer ersten Epitaxieschicht, die auf das Stabilisierungselement aufgebracht wird, eine Membran oberhalb des ersten Bereichs erzeugt. Wenigstens ein Teil des ersten Bereichs dient in einem weiteren Verfahrensschritt dazu, eine Kaverne unterhalb des Stabilisierungselement zu erzeugen. Der Kern der Erfindung besteht nun darin, das strukturierte Stabilisierungselement mittels einer zweiten Epitaxieschicht, die auf dem Halbleiterträger aufgebracht wird, zu erzeugen.
Abstract:
The invention relates to the production of a micromechanical component, comprising a substrate (10), made from a substrate material with a first doping type (p), a micromechanical functional structure arranged in the substrate (10) and a cover layer for the at least partial covering of the micromechanical functional structure. The micromechanical functional structure comprises regions (15; 15a; 15b; 15c; 730; 740; 830) made from the substrate material with a second doping type (n), at least partially surrounded by a cavity (50; 50a-f) and the cover layer comprises a porous layer (30) made from the substrate material.