The invention discloses an SAW-MEMS (surface acoustic waves-micro electro mechanical system) acceleration sensor which relates to the field of microelectronic inertial components. The acceleration sensor comprises an SAW metal interdigital transducer, a quartz plate and a silicon substrate, wherein the quartz plate is provided with a micro cantilever, and the silicon substrate is provided with a preset groove; the SAW metal interdigital transducer is manufactured on the micro cantilever in the quartz plate; the micro cantilever is bonded on the silicon substrate provided with the preset groove; the quartz plate is thinned through bonding with another silicon substrate without groove firstly, then transferred to the silicon substrate provided with the preset groove by using a bonding process; the SAW metal interdigital transducer is manufactured on the part, corresponding to the preset groove, of the quartz plate; and the micro cantilever structure is etched on the quartz plate, so that the SAW metal interdigital transducer is arranged on the micro cantilever. Because the acceleration sensor disclosed by the invention is prepared by using an MEMS process, the acceleration sensor is small in component size and suitable for mass production, therefore, the acceleration sensor provided by the invention is high in reliability, large in sensitive range, low in power consumption, high in precision, small in size and easy to package.

SAW-MEMS (surface acoustic waves-micro electro mechanical system) acceleration sensor and manufacturing method thereof

The invention discloses a method for machining an MEMS acceleration sensor, uses a silicon wafer of a crystal orientation as substrate silicon, etches a first cavity having a first upper surface and a first lower surface on the substrate silicon and a second cavity having a second upper surface and a second lower surface, the first cavity and the second cavity are communicated with each other, a part of the substrate silicon, which is located at an upper side of the first cavity, is used as a mass block of the acceleration sensor, a part which is located at an upper side of the second cavity is used as a cantilever beam of the acceleration sensor, and the thickness of the mass block is larger than that of the cantilever beam. The method is a lowcost MEMS acceleration sensor machining method; and consistency of performance of acceleration sensors on the same wafer is high.

Method for machining MEMS acceleration sensor and acceleration sensor

The invention discloses a silicon-silicon-bonding-based pressure sensor capable of isolating a packaging stress. The pressure sensor includes a chip layer and a support layer. A lug used for silicon-silicon bonding is etched on the surface of the support layer. Gaps exist between other areas of the support layer and the chip layer. The structure is capable of avoiding too much consideration of material selection (such as a packing substrate of low stress and an adhesive of low stress) so that high-efficiency thermal isolation is realized comparatively easily and larger shock can be resisted and thus the pressure sensor is wider in application occasions.

Silicon-silicon-bonding-based pressure sensor capable of isolating packaging stress

The invention provides a production method of a cavity-SIO (Silicon On Insulator). The production method comprises the following steps: providing a semiconductor substrate with a cavity pattern; providing an SOI silicon slice with top silicon; performing silicon-silicon bonding between the surface of the SOI silicon slice with top silicon and the surface of semiconductor substrate with the cavity pattern; and respectively removing all materials (except the top silicon) from the SOI silicon slice by etching. According to the production method of the cavity-SOI, the SOI silicon slice and the semiconductor substrate are bonded, and then materials (except the top silicon) are moved from the SOI silicon slice by etching, so that the size range of the cavity is enlarged, and the size of the cavity is not affected by the thickness of the top silicon, meanwhile the smallest thickness of the top silicon is reduced further, the problem of damage or falloff of the top silicon is avoided when the cavity with a large area is produced, and the reliability of subsequent processes and the product quality are improved.

Production method of cavity-SOI (Silicon On Insulator)

The invention relates to a sensing acceleration sensor with temperature compensation based on acoustic surface waves. The sensor comprises a shell and a shell cover which are connected in a sealing mode and further comprises a piezoelectric substrate, a piezoelectric film, a base and three acoustic surface wave resonators. The piezoelectric film is arranged on the upper surface of the piezoelectric substrate, the base is fixed on the bottom face in the shell, one end of the piezoelectric substrate is a fixed end, the other end of the piezoelectric substrate is an overhanging end, one end of the piezoelectric film and the fixed end of the piezoelectric substrate are both fixed to the base, and are higher than the bottom face in the shell, at least one acoustic surface wave resonator is arranged on the upper surface of the piezoelectric film, and the surplus acoustic surface wave resonators are arranged between the piezoelectric film and the piezoelectric substrate, resonant frequencies of the three acoustic surface wave resonators are different, the acoustic surface waves generated by the three acoustic surface wave resonators are spread in the direction x, and the direction x is the extending direction from the fixed end of the piezoelectric substrate to the overhanging end of the piezoelectric substrate. The sensing acceleration sensor has the advantages of being capable of monitoring acceleration and temperature and high in measuring precision.

Sensing acceleration sensor with temperature compensation based on acoustic surface waves

The utility model discloses an SAW-MEMES (surface acoustic wave micro-electromechanical system) acceleration sensor and relates to the field of micro-electronic inertia devices. The SAW-MEMES acceleration sensor comprises an SAW metal interdigital transducer, a quartz plate with a micro-cantilever beam and a silicon substrate preinstalled with a groove, the SAW metal interdigital transducer is arranged on the micro-cantilever beam in the quartz chip, the micro-cantilever beam is bonded onto the silicon substrate preinstalled with the groove, the quartz chip is transferred onto the silicon substrate preinstalled with the groove by the bonding technology after being bonded with another silicon substrate without a groove and being thinned, an SAW interdigital transducer is arranged at a position on the quartz chip corresponding to the preinstalled groove, and a micro-cantilever beam structure is carved on the quartz chip, so that the SAW interdigital transducer can be arranged on the micro-cantilever beam. The SAW-MEMES acceleration sensor adopts the MEMES technology, is suitable for batch production and has small-sized device. Accordingly, the acceleration sensor is high in reliability, wide in sensitive range, low in power consumption, high in accuracy, small in size and easy to be packed.

SAW-MEMES (surface acoustic wave micro-electromechanical system) acceleration sensor

The invention discloses a passive SAW (surface acoustic wave) accelerometer and an acceleration test method. The accelerometer comprises a force converter 2, a SAW device 1, antennas 8 and signal connecting lines 9, the SAW device 1 comprises a transducer 3, a first reflecting grating 4a and a second reflecting grating 4b, two electrodes of the transducer are connected with the antennas for signal transceiving through the signal connecting lines, and the force converter 2 comprises a cantilever beam 5, a mass block 6 and a fixing block 7. During acceleration input, the mass block generates inertia force and inertia moment to the fixing block, the moment enables the cantilever beam to be in deflection deformation around the fixing block and transmission time of an SAW signal on the surface of a substrate to vary, a value of input acceleration can be obtained by resolving variation of the transmission time, signal transceiving and energy transfer are both completed through the antennas, and accordingly passive detection of acceleration is achieved.

Jijun Bu

Papers

SAW-MEMS (surface acoustic waves-micro electro mechanical system) acceleration sensor and manufacturing method thereof

SAW-MEMES (surface acoustic wave micro-electromechanical system) acceleration sensor

Passive SAW (surface acoustic wave) accelerometer and acceleration test method