In-plane piezoresistive acceleration sensor with self-detection function and manufacturing method thereof

Abstract

The invention provides an in-plane piezoresistive type acceleration transducer having a self-detecting function and a manufacturing method therefor. The in-plane piezoresistive type acceleration transducer is manufactured based on an SOI wafer; the SOI wafer is orderly provided with a substrate, a middle oxide layer and a device layer; via side surface doping operation, a piezoresistive strip is formed on a side wall of a partial cantilever beam of the acceleration transducer, the side wall of the partial cantilever beam forms a self-detecting electrode, and the piezoresistive strip formed on the side wall can help reduce axial direction crosstalk; via a self-detecting mode, electrostatic force is used for simulating deformation, caused by acceleration, of the cantilever beam of the acceleration transducer; performance of the acceleration transducer can therefore be detected, and the detecting mode is completely compatible with an IC detecting probe bench. The acceleration transducer which adopts a front side release mode is high in processing consistency and small in occupied space. The invention also provides a manufacture method for the in-plane piezoresistive type acceleration transducer having the self-detecting function, and a structure and processing technologies for the in-plane piezoresistive type acceleration transducer capable of conducting wafer level self detection can be realized.

Description

technical field [0001] The invention relates to semiconductor manufacturing technology, in particular to an in-plane piezoresistive acceleration sensor with self-detection function and a manufacturing method thereof. Background technique [0002] At present, wafer-level calibration and testing of piezoresistive acceleration sensors is very difficult. There is no mature technology in the industry. Some test manufacturers (such as AFORE in Finland) provide wafer-level piezoresistive acceleration test solutions, but special test fixtures and probe cards need to be customized, so that the investment in fixed assets and High cost. [0003] At present, the piezoresistive acceleration sensor can only be tested at the module level by using the test bench after being packaged into a module product. Once the acceleration sensor fails, the loss includes not only the acceleration sensor, but also the packaging cost of the module and other components integrated in the module, such as t...

AI Technical Summary

Problems solved by technology

However, it can only grow N-type doped piezoresistive strips, and N-type doped piezoresistive strips have asymmetrical stress sensitivity coefficients, so the manufactured sensors have poor linearity

Images