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:
A method producing a microelectromechanical component. A dielectric layer is structured on an upper side of a substrate forming a grating, and a blind hole is formed beneath the grating. A cover layer is arranged on the dielectric layer closing the blind hole. A layer sequence is arranged on the cover layer and above the blind hole. Functional structures are formed in the layer sequence and an access channel extending through the layer sequence to the blind hole is formed. A further substrate is connected to the substrate. The functional structures are enclosed in a cavity, connected to the blind hole, between the substrate and the further substrate. Another blind hole is formed on an underside of the substrate. The blind hole is opened in the region of the other blind hole. A cavity internal pressure is set, and the blind hole is closed.
Abstract:
A process for manufacturing a MEMS pressure sensor having a micromechanical structure envisages: providing a wafer having a substrate of semiconductor material and a top surface; forming a buried cavity entirely contained within the substrate and separated from the top surface by a membrane suspended above the buried cavity; forming a fluidic-communication access for fluidic communication of the membrane with an external environment, set at a pressure the value of which has to be determined; forming, suspended above the membrane, a plate made of polysilicon, separated from the membrane by an empty space; and forming electrical-contact elements for electrical connection of the membrane and of the plate, which are designed to form the plates of a sensing capacitor, the value of capacitance of which is indicative of the value of pressure to be detected. A corresponding MEMS pressure sensor having the micromechanical structure is moreover described.
Abstract:
A method manufactures a gas sensor integrated on a semiconductor substrate. The method includes: realizing a first plurality of openings in the semiconductor substrate; realizing a crystalline silicon membrane suspended on the semiconductor substrate, forming an insulating cavity buried in the substrate; realizing a second plurality of openings in the semiconductor substrate, so as to totally suspend on the semiconductor substrate the crystalline silicon membrane; realizing, through a thermal oxidation process of the totally suspended crystalline silicon membrane, a suspended dielectric membrane; realizing, through selective photolithography, a heating element; realizing, through selective photolithography, electrodes and a pair of electric contacts; and selectively realizing, above the electrodes, a sensitive element by compacting layers of metallic oxide through a sintering process generated in the gas sensor by connecting the electrodes to a voltage generator.
Abstract:
A manufacturing method for a micromechanical semiconductor element includes providing on a semiconductor substrate a patterned stabilizing element having at least one opening. The opening is arranged such that it allows access to a first region in the semiconductor substrate, the first region having a first doping. Furthermore, a selective removal of at least a portion of the semiconductor material having the first doping out of the first region of the semiconductor substrate is provided. In addition, a membrane is produced above the first region using a first epitaxy layer applied on the stabilizing element. In a further method step, at least a portion of the first region is used to produce a cavity underneath the stabilizing element. In this manner, the present invention provides for the production of the patterned stabilizing element by means of a second epitaxy layer, which is applied on the semiconductor substrate.
Abstract:
A method for manufacturing a semiconductor substrate of a first concentration type is described, which comprises at least a buried insulating cavity, comprising the following steps: forming on the semiconductor substrate a plurality of trenches, forming a surface layer on the semiconductor substrate in order to close superficially the plurality of trenches forming in the meantime at least a buried cavity in correspondence with the surface-distal end of the trenches.
Abstract:
Proposed is a method for manufacturing micromechanical sensors and sensors manufactured by this method, where openings (2) are introduced into a semiconductor substrate (1). After the openings (2) are introduced into the semiconductor substrate (1), a subsequent temperature treatment is carried out, in which the openings (2) are converted into voids in the depth of the substrate (1).
Abstract:
A process for micromachining capillaries was having circular cross-sections in glass substrates. Microchannels are isotropically etched into a flat glass substrate, resulting in a semi-circular half-channel (or a rectangle with rounded corners). A second flat glass substrate is then fusion bonded to the first substrate, producing sealed microchannels with rounded bottom corners and a flat top surface having sharp corners. The process is completed by annealing at a sufficiently high temperature (approximately 750 C.) to allow surface tension forces and diffusional effects to lower the over-all energy of the microchannels by transforming the cross-section to a circular shape. The process can be used to form microchannels with circular cross-sections by etching channels into a glass substrate, then anodically bonding to a silicon wafer and annealing. The process will work with other materials such as polymers.
Abstract:
In a method for manufacturing a semiconductor pressure sensor, after a reference pressure chamber is formed inside a semiconductor substrate and a diaphragm is formed from a part of the semiconductor substrate, a heat treatment is performed to form an insulation film, an element, or the like on the semiconductor substrate. At that time, a heat treatment temperature is controlled to be lower than (null430P0null1430)null C. where P0 is an internal pressure (atm) of the reference pressure chamber at a room temperature. Accordingly, crystal defects can be prevented from being produced in the diaphragm.