[2024] Ultrasonic theranostics - imaging and neuromodulation in the same CMOS chip.

In the field of medical ultrasound technology, the dual requirements of imaging and therapeutic applications often necessitate the use of separate transducer arrays due to conflicting demands on transducer quality factors(Q-factor), leading to space limitations.

While in imaging applications, broadband pulses are needed to produce short ultrasound pulses towards high imaging resolution (low Q-factor), neuromodulation applications require long narrowband pulses (high Q-factor) for efficient neurostimulation. Typically, the Q-factor of piezoelectric ultrasound transducers is tuned by microfabricating either damping (low Q-factor) or reflective (high Q-factor) acoustic backing layers. However, in the context of wearable and minimally invasive ultrasound imaging and neuromodulation devices, it would be beneficial to have both features implemented in the same chip. This makes the design and microfabrication of optimal backing layers for both applications not feasible.

In this proposal, we aim to address this challenge by investigating methods for electronically controlling the Q-factor of piezoelectric transducer elements in an array, thus enabling multifunctionality within a single transducer array [1] [2]. Previous work in the group demonstrated a closed-loop circuit to automatically control the quality factor of piezoelectric transducers, which was implemented in a printed circuit board. The objective of this thesis is to integrate an improved version of the design into an integrated circuit and to expand this technique from a single transducer to an array of transducers, including beamforming capabilities.

Assignment

1.      Review existing literature on piezoelectric transducer electronic Q-factor control methods

2.      Design and simulate electronic circuits (IC design) for controlling the Q-factor of piezoelectric transducer arrays.

3.      If time allows, tape-out the circuit and perform electrical and acoustic testing.

Requirements

MSc students from Microelectronics with focus on analog and mixed-signal IC design.

Interested students should include their CV, the list of courses attended, and a motivation letter, and send it to Tiago Costa (t.m.l.dacosta@tudelft.nl) and Masoumeh Aqamolaei (m.aqamolaei@tudelft.nl).

Contact

Last modified: 2024-04-10