Method of using film transfer technology to manufacture film bulk acoustic wave device

Abstract

The invention provides a method of using a film transfer technology to manufacture a film bulk acoustic wave device. The method comprises the following steps of 1) providing an oxide single crystal substrate; 2) carrying out ion implantation from an injection surface to an internal portion of the oxide single crystal substrate and then forming a lower electrode on the injection surface; or forming the lower electrode on the injection surface and then carrying out ion implantation from the injection surface to the internal portion of the oxide single crystal substrate; 3) providing support substrate and bonding a structure acquired from the step 2) with the support substrate; 4) peeling a part of oxide single crystal substrate along a defect layer so as to acquire an oxide single crystal film, and transferring the oxide single crystal film and the lower electrode to the support substrate; 5) corroding the support substrate so as to form a cavity; and 6) forming an upper electrode on an oxide single crystal film surface. The invention provides a new method to manufacture a film bulk acoustic wave filter core structure of a metal electrode-single crystal oxide-metal electrode, and a problem that the single crystal oxide can not be manufactured between the metal electrodes is effectively solved.

Description

technical field [0001] The invention belongs to the technical field of semiconductor preparation, and in particular relates to a method for preparing a thin-film bulk acoustic wave device by using thin-film transfer technology. Background technique [0002] With the development of science and technology, thin film bulk acoustic wave devices have been widely used in more and more areas. In the prior art, the fabrication method of thin-film bulk acoustic wave devices is generally to deposit an oxide dielectric thin film on the metal bottom electrode, and then prepare a metal top electrode on the oxide thin film to form a metal-oxide-metal sandwich structure. The key technology is the preparation of oxide dielectric thin films. The common preparation methods of oxide dielectric thin films include pulsed laser deposition, magnetron sputtering, atomic layer deposition, and thermal evaporation. However, there are many problems in these traditional thin film preparation methods. F...

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Problems solved by technology

However, there are many problems in these traditional thin film preparation methods, for example, it is generally necessary to grow oxide thin films at relatively high temperatures, and it is difficult to be compatible with existing CMOS processes

In addition, due to factors such as lattice mismatch, thermal mismatch, and interface defects, these traditional thin film preparation methods cannot grow high-quality single crystal oxide thin films on polycrystalline metal bottom electrodes.

However, the problems of amorphous or polycrystalline thin films prepared by traditional thin film preparation methods include: on the one hand, there are many different defects in both amorphous and polycrystalline thin films; The distribution in the thin film is random, which is a bottleneck that is difficult to break through for reducing the size of the device, stabilizing and optimizing the device parameters, and reliability research.

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