Abstract:
Mit der vorliegenden Erfindung wird ein Verfahren zur Herstellung einer mikromechanischen Membranstruktur (11) mit feststehendem Gegenelement (12) vorgeschlagen, das von einem p-dotierten Si- Substrat (1) ausgeht. Dieses Verfahren umfasst die folgenden Prozessschritte - n-Dotierung mindestens eines zusammenhängenden gitterförmigen Bereichs (2) der Substratoberfläche; (Fig. Ia) porös Ätzen eines Substratbereichs (3) unterhalb der n-dotierten Gitterstruktur (2); (Fig. lb-c) Oxidation des porösen Siliziums; (Fig. Id) - Erzeugen mindestens einer Opferschicht (5) über der n-dotierten Gitterstruktur (2); (Fig. Ie) Abscheidung und Strukturierung mindestens einer dicken Epitaxieschicht (7); (Fig. lf-g) Entfernen der Opferschicht (5) zwischen der dicken Epitaxieschicht (7) und der n-dotierten Gitterstruktur (2) und Erzeugen einer Kaverne (10) im Si-Substrat (1) unterhalb der n- dotierten Gitterstruktur (2) durch Entfernen des oxidierten porösen Siliziums (oxPorSi); (Fig. Ih) so dass die freigelegte n-dotierte Gitterstruktur (2) eine Membranstruktur (11) bildet und in der strukturierten dicken Epitaxieschicht (7) mindestens ein feststehendes Gegenelement (12) ausgebildet ist.
Abstract:
The invention relates to a method for production of an operation system for an optical component, comprising the engraving of a first face of a component to form blocks thereon, the engraving of a second face of the component to release a membrane of the same material as the blocks and the production of operating means of the blocks and the membrane.
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:
L'invention concerne notamment un procédé de réalisation de motifs dans une couche à graver (410), à partir d'un empilement comprenant au moins la couche à graver (410) et une couche de masquage(420) surmontant la couche à graver (410), la couche de masquage(420) présentant au moins un motif (421), le procédé comprenant au moins: a) une étape de modification d'au moins une zone (411) de la couche à graver (410) par implantation d'ions (430) au droit de l'au moins un motif (421); b) au moins une séquence d'étapes comprenant: b1) une étape d'élargissement (440) de l'au moins un motif (421) selon un plan dans lequel s'étend principalement la couche à graver (410); b2) une étape de modification d'au moins une zone (411', 411'') de la couche à graver (410) par implantation d'ions (430) au droit de l'au moins un motif (421) élargi, l'implantation étant effectuée sur une profondeur inférieure à la profondeur d'implantation de l'étape précédente de modification; c) une étape de retrait (461, 462) des zones modifiées (411, 411', 411''), le retrait comprenant une étape de gravure des zones modifiées (411, 411', 411'') sélectivement aux zones non modifiées (412) de la couche à graver (410).
Abstract:
L'invention concerne un procédé de réalisation d'un système d'actionnement pour un composant optique comportant la gravure d'une première face d'un composant, pour y former des plots, la gravure d'une deuxième face du composant, pour dégager une membrane dans le même matériau que les plots, la réalisation des moyens d'actionnement des plots et de la membrane.
Abstract:
The invention relates to a micromechanical sensor and to a corresponding production method, comprising the following steps: a) preparing a doped semiconductor wafer (4); b) applying an epitaxial layer (1) that is doped in such a way that a jump in the charge carrier density in the interface (11) between the semiconductor wafer and the epitaxial layer occurs; c) optionally etching ventilation holes (2) traversing the epitaxial layer and optionally filling the ventilation holes with a sacrificial material; d) depositing at least one sacrificial layer (9), at least one spacing layer (10), a membrane (5) and optionally a semiconductor circuit (8) on the top side of the epitaxial layer using a technology known per se, wherein the semiconductor circuit may be applied after the membrane is formed or while depositing the layers required to form the membrane; e) etching a hole (6) on the back part of the sensor, wherein the etching method is selected in such a way that etching advances in the direction of the top side and ceases in the interface between the wafer (4) and the epitaxial layer (1) by changing charge carrier concentration. The invention also relates to the utilization of the micromechanical sensor in pressure sensors or microphones.
Abstract:
A method of anodizing a silicon substrate includes a step of forming an n-type silicon buried layer (21) of n-type silicon in a predetermined region in a first surface of a p-type monocrystalline silicon substrate (2). The n-type silicon buried layer (21) has at its central portion an opening (21a) for a current to flow. N-type silicon layers (4, 6) are formed on the surface of the p-type monocrystalline silicon substrate (2) and on the n-type silicon buried layer (21). Silicon diffusion layers (5, 7) containing p-type impurities at a high concentration are formed in predetermined regions of the n-type silicon layers (4, 6) and are in contact with the n-type silicon buried layer (21). An electrode layer (13) is formed on the back surface of the p-type silicon substrate (2). The anode of a DC power source (15) is connected to the electrode layer (13), and the cathode is connected to an electrode (23) opposed to the p-type silicon substrate (2). A current is made to flow concentratedly into a region corresponding to the opening (21a) of the n-type silicon layer (4) in the direction from the back surface toward the front surface of the p-type monocrystalline silicon substrate (2) immersed in a hydrofluoric acid solution, so that the region is turned porous.
Abstract:
A method of forming an undercut microstructure includes: forming an etch mask on a top surface of a substrate; forming, on a top surface of the etch mask, an ion implantation mask having a top surface that is smaller than the top surface of the etch mask and that does not extend beyond the top surface of the etch mask; ion implanting the substrate in the presence of the etch mask and the ion implantation mask so that a damaged region is generated at a depth below an area of the surface that is not masked by the ion implantation mask; and etching the surface of the substrate until the damaged region is removed.
Abstract:
The present invention illustrates a bulk silicon etching technique that yields straight sidewalls, through wafer structures in very short times using standard silicon wet etching techniques. The method of the present invention employs selective porous silicon formation and dissolution to create high aspect ratio structures with straight sidewalls for through wafer MEMS processing.
Abstract:
A semiconductor device and a method of producing the same is disclosed, in which a through hole is formed in the upper surface of a semiconductor substrate from the lower surface thereof, and an opening of a desired size is formed in a desired position on the upper surface of the substrate. A guide that functions as an etching stopper is formed in the semiconductor substrate. An opening having a width W2 is formed in the guide. The opening faces an opening in a mask used in the formation of a through hole, and the width W2 thereof is narrower than a width W4 of the opening in the mask. The direction in which etching progresses is controlled by the opening formed in the guide as etching is conducted from a lower surface of the substrate to an upper surface of the substrate, and thus deviations in the width W1 and position of an opening in the upper surface of the substrate can be controlled.