Abstract: Method of encapsulating a semiconductor structure comprising providing a semiconductor structure comprising an opto-electric element located in a cavity formed between a substrate and a cap layer, the cap layer being made of a material transparent to light, and having a flat upper surface; forming at least one protrusion on the cap layer; bringing the at least one protrusion of the cap layer in contact with a tool having a flat surface region, and applying a opaque material to the semiconductor structure where it is not in contact with the tool; and removing the tool thereby providing an encapsulated optical semiconductor device having a transparent window integrally formed with the cap layer.

Abstract: A sensor assembly for sensing infrared radiation and its manufacture are described. The sensor comprises at least one sensing element provided on or embedded in a substrate extending substantially in a substrate plane, a cap for covering the at least one sensing element, the cap comprising an upper wall for receiving radiation incident on the sensor assembly and a plurality of cavity walls arranged to define a cavity between the cap and the substrate for hosting the sensing element. At least one of said cavity walls subtends an angle with respect to the receiving upper wall so as to induce total internal reflection on said cavity walls for radiation incident thereon.

Abstract: The invention relates to an infrared thermal sensor comprising a substrate having a cavity, a cavity bottom wall formed by a continuous substrate surface. The sensor comprises a membrane adapted for receiving heat from incident infrared radiation, a beam suspending the membrane, and a thermocouple. This membrane comprises openings extending through the membrane for facilitating the passage of an anisotropic etchant for etching the cavity during manufacture. Each opening has a cross-section with a length to width ratio of at least 4. The width direction of respectively a first and a second set of openings is oriented according to respectively a first crystallographic orientation and a second crystallographic orientation, these orientations corresponding to different directions lying in loosely packed crystal lattice faces of the semiconductor substrate.

Abstract: An infrared thermal sensor for detecting infrared radiation, comprising a substrate and a cap structure together forming a sealed cavity, the cavity comprising a gas at a predefined pressure; a membrane arranged in said cavity for receiving infrared radiation; a plurality of beams for suspending the membrane; a plurality of thermocouples for measuring a temperature difference between the membrane and the substrate; wherein the ratio of the thermal resistance between the membrane and the substrate through the thermocouples, and the thermal resistance between the membrane and the substrate through the beams and through the gas is a value in the range of 0.8 to 1.2. A method of designing such a sensor, and a method of producing such a sensor is also disclosed.

Abstract: An infrared thermal sensor for detecting infrared radiation is described. It comprises a substrate and a cap structure together forming a sealed cavity. A membrane is suspended therein by a plurality of beams, each beam comprising at least one thermocouple arranged therein or thereon for measuring a temperature difference between the membrane and the substrate. At least two beams have a different length and each of the thermocouples have a substantially same constant width to length ratio such that the thermal resistance measured between the membrane and the substrate is substantially constant for each beam, and such that the electrical resistance measured between the membrane and the substrate is substantially constant for each beam. The beams may be linear, and be oriented in a non-radial direction.