Abstract:
There is provided a method for forming a composite cavity and a composite cavity formed using the method. The method comprises the following steps: providing a silicon substrate (101); forming an oxide layer on the front side thereof; patterning the oxide layer to form one or more grooves (103), the position of the groove (103) corresponding to the position of small cavity (109) to be formed; providing a bonding wafer (104), which is bonded to the patterned oxide layer to form one or more closed micro-cavity structures (105) between the silicon substrate (101) and the bonding wafer (104); forming a protective film (106) over the bonding wafer (104) and forming a masking layer (107) on the back side of the silicon substrate (101); patterning the masking layer (107), the pattern of the masking layer (107) corresponding to the position of a large cavity (108) to be formed; using the masking layer (107) as a mask, etching the silicon substrate (101) from the back side until the oxide layer at the front side thereof to form the large cavity (108) in the silicon substrate (101); and using the masking layer (107) and the oxide layer as a mask, etching the bonding wafer (104) from the back side through the silicon substrate (101) until the protective film (106) thereover to form one or more small cavities (109) in the bonding wafer (104). The uniformity of thickness of the semiconductor medium layer where the small cavity (109) in the composite cavity is located is well controlled by the present invention.
Abstract:
A membrane-based sensor in one embodiment includes a membrane layer including an upper surface and a lower surface, a backside trench defined on one side by the lower surface, a central cavity defined on a first side by the upper surface, a cap layer positioned above the central cavity, and a first spacer extending from the upper surface to the cap layer and integrally formed with the cap layer, the first spacer defining a second side of the central cavity and an inner membrane portion of the membrane layer.
Abstract:
Measures are provided, by which mechanical stresses within the diaphragm structure of a MEMS component may be intentionally dissipated, and which additionally enable the implementation of diaphragm elements having a large diaphragm area in comparison to the chip area. The diaphragm element is formed in the layer structure of the MEMS component. It spans an opening in the layer structure and is attached via a spring structure to the layer structure. The spring structure includes at least one first spring component, which is oriented essentially in parallel to the diaphragm element and is formed in a layer plane below the diaphragm element. Furthermore, the spring structure includes at least one second spring component, which is oriented essentially perpendicularly to the diaphragm element. The spring structure is designed in such a way that the area of the diaphragm element is greater than the area of the opening which it spans.
Abstract:
A microphone includes a base, a micro electro mechanical system (MEMS) device disposed on the base, and a front end processing apparatus disposed on the base and coupled to the MEMS device, the front end processing apparatus being configured to convert analog signals received from the MEMS device into digital signals. The microphone also includes a DSP apparatus, the DSP apparatus being a digital programmed device with a computer memory, the DSP apparatus configured to process the digital signals received from the front end processing apparatus. The MEMS device, the front end processing apparatus, and DSP apparatus are enclosed within a single microphone enclosure or assembly. During operation the DSP apparatus generates DSP noise. The DSP apparatus includes a noise reduction structure that substantially prevents the DSP noise from reaching or interfering with the operation of the MEMS device or the front end processing apparatus.
Abstract:
A micromechanical structure, comprising a substrate having a through hole; a residual portion of a sacrificial oxide layer peripheral to the hole; and a polysilicon layer overlying the hole, patterned to have a planar portion; a supporting portion connecting the planar portion to polysilicon on the residual portion; polysilicon stiffeners formed extending beneath the planar portion overlying the hole; and polysilicon ribs surrounding the supporting portion, attached near a periphery of the planar portion. The polysilicon ribs extend to a depth beyond the stiffeners, and extend laterally beyond an edge of the planar portion. The polysilicon ribs are released from the substrate during manufacturing after the planar region, and reduce stress on the supporting portion.
Abstract:
A method for fabricating a MEMS-IC device structure can include receiving a CMOS substrate comprising a plurality of CMOS circuits and a surface portion. A MEMS substrate having at least one MEMS device can be received and coupled to the CMOS substrate. The MEMS substrate and the surface portion of the CMOS substrate can be encapsulated with a molding material, which forms a top surface. A first plurality of vias can be created in the molding material from the top surface to the surface portion of the CMOS substrate. A conductive material can be disposed within the first plurality of vias such that the conductive material is electrically coupled to a portion of the CMOS substrate. A plurality of interconnects can be formed from the conductive material to the top surface of the molding material and a plurality of solder balls can be formed upon these interconnects.
Abstract:
A sensor structure may include a first suspended structure and a second suspended structure disposed from the first suspended structure to form a volume. The first suspended structure and the second suspended structure may be arranged relative to each other such that a received pressure wave entering the volume between the first suspended structure and the second suspended structure generates a displacement of the first suspended structure to a first direction and a displacement of the second suspended structure to a second direction different from the first direction and the displacement may generate a measurable signal.
Abstract:
A multi-MEMS module is specified which can be produced expediently and enables a smaller design. The module comprises a housing having an interior and a first and a second opening, a first MEMS chip and a second MEMS chip. The first MEMS chip is acoustically coupled to the first opening. The second MEMS chip is acoustically coupled to the second opening.
Abstract:
According to an embodiment, a microelectromechanical systems (MEMS) transducer includes a first electrode, a second electrode fixed to an anchor at a perimeter of the second electrode, and a mechanical support separate from the anchor at the perimeter of the second electrode and mechanically connected to the first electrode and the second electrode. The mechanical support is fixed to a portion of the second electrode such that, during operation, a maximum deflection of the second electrode occurs between the mechanical structure and the perimeter of the second electrode.