Method for generating a flow in a microdrop and device for implementing the method

A method for generating agitation in a microdrop of fluid, the volume of which is greater than a few tens of nanolitres, said method including:

• implementing an actuation device using sound waves, said actuation device comprising a support on and from which said microdrop of fluid is deposited and removed, and a resonator suitable for converting an electrical sine-wave signal applied at its terminals into sound waves, the method further including wherein:
• the resonator of the actuation device implemented is a high overtone bulk acoustic resonator (HBAR), the HBAR having a quality factor Q of at least 100 in air and containing said support, said support being flat and coated with a layer of dielectric material;
• said HBAR is associated with a modulable electronic device suitable for generating high-frequency waves;
• and the method includes the following steps:
• depositing the microdrop of fluid on said support;
• generating an electrical sine-wave signal(S) by controlling the modulable electronic device, said generated electrical sine-wave signal(S) having a frequency selected using the modulable electronic device, wherein said frequency is greater than or equal to 100 MHz and less than or equal to 4 GHz;
• and
• converting the electrical sine-wave signal(S) having said selected frequency into high-frequency sound waves (OA) using said HBAR, the high-frequency sound waves (OA) having a natural resonance generating a given agitation in the microdrop of fluid.