Abstract:
A process is disclosed for producing spatially patterned components from a body. On the backside of the body, a retardation layer with openings is provided for retarding a removal of the material of the body, and areas of migration-capable material are deposited. The body is subjected to a thermal migration process to form migration regions. Then, in a single material removal step, the components are separated from the body and the migration regions are exposed.
Abstract:
A micro-electro-mechanical device formed in a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region above the first buried cavity; and a second buried cavity extending in the sensitive region. A decoupling trench extends from a first face of the monolithic body as far as the first buried cavity and laterally surrounds the second buried cavity. The decoupling trench separates the sensitive region from a peripheral portion of the monolithic body.
Abstract:
A differential pressure detection element includes: a support portion having an opening; a cantilever portion supported in a cantilever manner by the support portion so as to protrude into the opening; a diffusion layer including a piezoresistive portion provided at a fixed end of the cantilever portion; a pair of wiring portions electrically connected to the diffusion layer; a first insulating layer covering the diffusion layer; and a second insulating layer laid on the first insulating layer. A linear expansion coefficient of the first insulating layer is smaller than a linear expansion coefficient of a material of which the cantilever portion is composed, and a linear expansion coefficient of the second insulating layer is larger than the linear expansion coefficient of the first insulating layer.
Abstract:
A micro-electro-mechanical device formed in a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region above the first buried cavity; and a second buried cavity extending in the sensitive region. A decoupling trench extends from a first face of the monolithic body as far as the first buried cavity and laterally surrounds the second buried cavity. The decoupling trench separates the sensitive region from a peripheral portion of the monolithic body.
Abstract:
An electrostatic MEMS element for flattening a drive side electrode surface and improving its performance as well as for improving degree of design freedom in a manufacturing process. A manufacturing method of the electrostatic MEMS element is also disclosed. Moreover, a GLV device using the MEMS element and a laser display using the GLV device are also disclosed. The electrostatic MEMS element includes a substrate side electrode and a beam having a drive side electrode driven by an electrostatic attracting force or electrostatic repulsive force functioning between the substrate side electrode and the drive side electrode. The substrate side electrode is formed in a conductive semiconductor region having impurities in the semiconductor substrate so as to constitute an electrostatic drive MEMS element.
Abstract:
A method for forming microscopic scale structures by selective etching of a doped substrate is disclosed. A substrate is prepared for etching by forming relatively deep doped substrate regions with substantially faster dissolution rates in selected etchants than the surrounding pure substrate. The doped regions are defined by depositing the dopants on the substrate using a lithographic process. Doped regions with high aspect ratios are produced by thermomigrating the deposited metal into the substrate. The substrate is then etched in an etchant that selectively removes the doped regions, while leaving the surrounding pure substrate essentially unetched. Thus, the doped region can be used to define a high aspect ratio feature, such as a microtubulc or micro-channel. Additionally, methods for forming more complex structures by depositing a variety of different dopants in a pattern on a substrate are disclosed. Combinations of the foregoing selective doping methods with a mask-and-etch process are further disclosed, useful for making structures such as a microscopic needle having a central microtubule for injecting fluids.
Abstract:
Processes for fabricating capacitive micromachined ultrasonic transducers (CMUTs) are described, as are CMUTs of various doping configurations. An insulating layer separating conductive layers of a CMUT may be formed by forming the layer on a lightly doped epitaxial semiconductor layer. Dopants may be diffused from a semiconductor substrate into the epitaxial semiconductor layer, without diffusing into the insulating layer. CMUTs with different configurations of N-type and P-type doping are also described.