Abstract: A wafer includes a wafer frontside surface and a region adjacent to the wafer frontside surface. The region includes oxygen precipitates and the wafer frontside includes a predetermined surface structure to form thereon a device with a desired property.

Abstract: In a method for manufacturing a piezoelectric oscillating circuit in thin film technology, wherein the oscillating circuit includes a predetermined natural frequency and a plurality of layers, first of all at least a first layer of the piezoelectric oscillating circuit is generated. Subsequently, by processing the first layer a frequency correction is performed. Subsequently, at least a second layer of the piezoelectric oscillating circuit is generated and processed for performing a second frequency correction.

Abstract: In a method for manufacturing a piezoelectric oscillating circuit in thin film technology, wherein the oscillating circuit includes a predetermined natural frequency and a plurality of layers, first of all at least a first layer of the piezoelectric oscillating circuit is generated. Subsequently, by processing the first layer a frequency correction is performed. Subsequently, at least a second layer of the piezoelectric oscillating circuit is generated and processed for performing a second frequency correction.

Abstract: A filter device and a method for fabricating filter devices can package filters, especially acoustic wave filters, by bonding a carrier (substrate) wafer carrying manufactured filters to another wafer referred to as a capping wafer. A capping wafer/substrate eliminates the need for a conventional package to protect the sensitive filters, which reduces both product size and product costs significantly. Even though additional packaging is possible (i.e. in plastic molded packages, or in glob-top packages), it is not required for the reliability of the filters.

Abstract: A filter circuit comprises a balanced port, an unbalanced port and a substrate. A series circuit of a filter stage and a balun is disposed between the balanced port and the unbalanced port. The balun and the filter stage are formed on the substrate.

Abstract: In a housing manufacturing method a base is provided with first contact elements with a photolithographically patternable layer that is patterned for exposing the contact elements. A chip with a micromechanical structure lying between second contact elements at the chip is provided with a photolithographically patternable layer which is patterned in order to provide a recess in the area of the micromechanical structure and in the area of the second contact elements. After joining the base and the chip the base is removed by etching.

Abstract: In a housing manufacturing method a base is provided with first contact elements with a photolithographically patternable layer that is patterned for exposing the contact elements. A chip with a micromechanical structure lying between second contact elements at the chip is provided with a photolithographically patternable layer which is patterned in order to provide a recess in the area of the micromechanical structure and in the area of the second contact elements. After joining the base and the chip the base is removed by etching.

Abstract: In a method for manufacturing a piezoelectric oscillating circuit in thin film technology, wherein the oscillating circuit includes a predetermined natural frequency and a plurality of layers, first of all at least a first layer of the piezoelectric oscillating circuit is generated. Subsequently, by processing the first layer a frequency correction is performed. Subsequently, at least a second layer of the piezoelectric oscillating circuit is generated and processed for performing a second frequency correction.

Abstract: A resonator apparatus has a piezoelectric resonator as well as an acoustic reflector which has a layer having a high acoustic impedance and a layer having a low acoustic impedance. The thickness of one layer is set different from a quarter of the wavelength in this layer at the operating frequency due to technological limitations in the manufacturing of this layer, and the thickness of the other layer is set dependent from the one layer, such that a predetermined minimum quality of the acoustic reflector is attained.

Abstract: A resonator apparatus has a piezoelectric resonator as well as an acoustic reflector which has a layer having a high acoustic impedance and a layer having a low acoustic impedance. The thickness of one layer is set different from a quarter of the wavelength in this layer at the operating frequency due to technological limitations in the manufacturing of this layer, and the thickness of the other layer is set dependent from the one layer, such that a predetermined minimum quality of the acoustic reflector is attained.

Abstract: A micromechanical differential pressure sensor device for measuring a pressure difference between two mutually separated spaces or media, in which two absolute pressure measuring devices are monolithically integrated on a single support substrate, in particular on a semiconductor chip. The absolute pressure measuring devices are preferably fabricated by surface micromachining.

Abstract: A method is disclosed for producing a micromechanical component. The micromechanical component has sensor holes, wherein at least one component protective layer and/or a spacer coating is applied on the component before separating the wafer into chips. The component protective layer sealingly covers at least the walls of the holes extending parallel to the surface of the wafer and perpendicular to the surface of the wafer and the spacer coating sealingly covers at least the walls of the holes extending parallel to the surface of the wafer.

Abstract: The invention relates to a micromechanical sensor and to a corresponding production method that includes the following steps: a) preparing a doped semiconductor wafer; b) applying an epitaxial layer that is doped in such a way that a jump in the charge carrier density in the interface between the semiconductor wafer and the epitaxial layer occurs; c) optionally etching ventilation holes traversing the epitaxial layer and optionally filling the ventilation holes with a sacrificial material; d) depositing at least one sacrificial layer, at least one spacing layer, a membrane and optionally a semiconductor circuit 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 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 interference betw

Abstract: A micromechanical structure, such as a sensor, includes a substrate, a diaphragm, a cavity, a sacrificial layer and a terminating structure. The terminating structure is cut away in the region of the diaphragm in such a way that a media opening is located above the diaphragm. The diameter of the cavity is smaller over the entire circumference of the cavity than the diameter of the opening. A method for manufacturing the micromechanical structure is also provided.

Abstract: A sensor, in particular a micromechanical pressure sensor, has two identical capacitive partial structures coupled to an evaluation circuit. In the case of in-phase driving, an additive signal is present as a pressure-dependent useful signal. In the case of in-antiphase driving, a difference signal is present as a diagnostic signal.

Abstract: A process which prevents abnormal WSi.sub.x oxidation during subsequent LPCVD insulator deposition and gate sidewall oxidation, uses an in-situ deposition of a thin amorphous silicon layer on top of the tungsten silicide as well as the deposition of an amorphous spacer after gate stack patterning, respectively.

Abstract: A procedure for forming uniformly recessed fills of trench structures that maintains a planar wafer surface without need of any intermediate or final planarization technique. The procedure relies on isotropical etches with high selectivities and the presence of a sacrificial layer. Its only design requirement is that all trenches must at least have one dimension smaller than twice the recess depth.

Abstract: A temperature control apparatus for single wafer etching tools comprising a cathode electrode, an isolation layer, and chuck means, respectfully, which are vertically stacked to support a wafer to be etched. A layer of thermoelectric elements is disposed between the isolation layer and the chuck means. The layer of thermoelectric elements comprises a center area closed loop of connected Peltier elements and an outer area closed loop of connected Peltier elements. The center area closed loop is coupled to a power source and is arranged to correspond to the center area of the wafer. The outer area closed loop is coupled to a power source and is arranged to correspond to the outer area of the wafer. Accordingly, the temperatures associated with each of the specific areas of the wafer are individually controlled by one of the closed loops.

Abstract: A non-contact in-situ temperature measurement apparatus for a single crystal substrate such as a semiconductor wafer using X-ray diffraction. Utilizing the Bragg condition for X-ray diffraction, the lattice constant of the semiconductor substrate can be determined either by measuring the diffraction angle for a monochromatic X-ray (monochromatic approach) or by measuring the wavelength of an X-ray diffracted with a certain scattering angle (polychromatic approach). The lattice constant, as a well-known function of temperature, is finally converted into the temperature of the semiconductor substrate.