Structure for growth of aluminum nitride with high scandium doping concentration

Abstract

The invention relates to a structure for growth of aluminum nitride with high scandium doping concentration, and belongs to the technical field of electromechanics. The structure sequentially comprises a silicon substrate, an adhesion layer, a lower electrode layer, an aluminum nitride seed layer, a low scandium-doped concentration aluminum scandium nitride seed layer and a high scandium-doped concentration aluminum scandium nitride piezoelectric layer from bottom to top. The high-scandium-doped-concentration aluminum-scandium nitride piezoelectric film grown by taking the structure as a corepreparation technology has good crystal growth quality, relatively low stress and relatively high piezoelectric coefficient, and a piezoelectric film device prepared on the basis has good performance;moreover, multiple seed layers are adopted to reduce interlayer lattice adaptation, improve the growth quality of the aluminum-scandium nitride crystal and reduce the stress of the film.

Description

technical field [0001] The invention belongs to the field of electromechanical technology, and relates to a structure for growing aluminum nitride with high scandium-doped concentration. Background technique [0002] Scandium-doped aluminum nitride piezoelectric film has the characteristics of high sound velocity, high temperature resistance, stable performance, and compatibility with CMOS technology. It is the known piezoelectric film material with the highest piezoelectric coefficient and has attracted widespread attention at home and abroad. MEMS devices based on scandium-doped aluminum nitride piezoelectric thin films have been widely used in the fields of sensors, resonators and energy harvesters. [0003] The aluminum scandium nitride piezoelectric film with high scandium doping concentration prepared by reactive magnetron sputtering method as the core technology, due to the large amount of scandium element, will produce lattice distortion compared with pure aluminum n...

AI Technical Summary

Problems solved by technology

[0003] The aluminum scandium nitride piezoelectric film with high scandium doping concentration prepared by reactive magnetron sputtering method as the core technology, due to the large amount of scandium element, will produce lattice distortion compared with pure aluminum nitride crystal, resulting in the growth of the film The c-axis orientation is poor, and the film stress is high, which will greatly reduce the piezoelectric coefficient of the film and the performance of the device.

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