Abstract: Charged particle sensing devices and methods of forming charged particle sensing devices are provided. The charged particle sensing device includes a source of charged particles, a plurality of collector electrodes for receiving a first portion of the charged particles and a grid formed around and spaced apart from the plurality of collector electrodes. The grid receives a second portion of the charged particles and directs backscattered charged particles, generated responsive to the second portion, to adjacent collector electrodes.

Abstract: Charged particle sensing devices and methods of forming charged particle sensing devices are provided. The charged particle sensing device includes a source of charged particles, a plurality of collector electrodes for receiving a first portion of the charged particles and a grid formed around and spaced apart from the plurality of collector electrodes. The grid receives a second portion of the charged particles and directs backscattered charged particles, generated responsive to the second portion, to adjacent collector electrodes.

Abstract: An all-silicon monolithic capacitive absolute pressure-sensing device and method for making the same. The device employs a single-crystal silicon diaphragm that serves at a flexible capacitor plate of a variable capacitor. The diaphragm is bonded to a single-crystal silicon wafer to overlie a cavity etched into the wafer. A fixed capacitor plate of the variable capacitor is formed by a heavily-doped region at the bottom of the cavity. A thin dielectric layer is grown on the fixed capacitor plate to complete the capacitor. The cavity has a minimal depth such that the fixed capacitor plate provides overpressure protection for the diaphragm. At least a portion of the operating range of the pressure sensor occurs while the diaphragm is contacting the doped region. As a result, the capacitive output signal of the pressure sensor is produced by changes in contact area between the diaphragm and a thin dielectric situated on the doped region in response to pressure applied to the diaphragm.

Abstract: A process for bulk micromachining a silicon wafer to form a silicon micromachined structure. The process involves the application of a protective film on one or more surfaces of the silicon wafer to protect metallization and circuitry on the wafer during the bulk micromachining process, during which a wet chemical etchant is employed to remove bulk silicon from a surface of the silicon wafer. The protective film is divinylsiloxane bisbenzocyclobutene (BCB), which has been found to be highly resistant to a wide variety of wet chemical etchants, and retains such resistant at elevated temperatures commonly preferred for bulk silicon etching. The degree to which this material is cured prior to etching is advantageously tailored to promote its resistance to the etchant and promote its adhesion to the silicon wafer.

Abstract: A method for making and vacuum packaging a silicon micromachined motion sensor, such as a gyroscope, at the chip level. The method involves micromachining a trench-isolated sensing element in a sensing chip, and then attaching a circuit chip to enclose the sensing element. Solder bumps serve to attach the circuit chip to the sensing chip, form a hermetic seal to enable vacuum-packaging of the sensor, and electrically interconnect the sensing chip with the circuit chip. Conductive runners formed on the enclosed surface of the circuit chip serve to electrically interconnect the sensing element with its associated sensing structures.

Abstract: A motion sensor including a sensing wafer with a bulk micromachined sensing element, and a capping wafer on which is formed the conditioning circuitry for the sensor. The sensing and capping wafers are configured such that, when bonded together, the capping wafer encloses the sensing element to form a monolithic sensor. The capping wafer is further configured to expose bond pads on the sensing wafer, and to enable singulation of the two-wafer stack into individual dies. Wire bonds can be made to both wafers, such that the sensor can be packaged in essentially any way desired.

Abstract: An all-silicon monolithic capacitive absolute pressure-sensing device and method for making the same. The device employs a single-crystal silicon diaphragm that serves at a flexible capacitor plate of a variable capacitor. The diaphragm is bonded to a single-crystal silicon wafer to overlie a cavity etched into the wafer. A fixed capacitor plate of the variable capacitor is formed by a heavily-doped region at the bottom of the cavity. A thin dielectric layer is grown on the fixed capacitor plate to complete the capacitor. The cavity has a minimal depth such that the fixed capacitor plate provides overpressure protection for the diaphragm. At least a portion of the operating range of the pressure sensor occurs while the diaphragm is contacting the doped region. As a result, the capacitive output signal of the pressure sensor is produced by changes in contact area between the diaphragm and a thin dielectric situated on the doped region in response to pressure applied to the diaphragm.