Mixed-signal Microelectronics (MsM)

System Investigation Digital Sigma Delta Converter

Within the framework of Inter-department Projects for MSc students this new project is proposed regarding the design of new ultrasound transducers, based on a novel deposition technology for piezo-electric transducers. Micro-components causing mechanical movement induced by electrical signals arrange under Micro-ElectroMechanical Systems, MEMS.

The Dutch startup company SolMateS in Enschede has developed a novel deposition technology for PZT. The question in this project concerns the requirements for the PZT layer properties such as homogeneity, thickness, chemical composition, and substrate properties. These specifications are imposed by the PZT MEMS device performance in the application.

Piezo-electric materials such as PZT expand, if a voltage is applied to it. This makes it possible to use PZT as a MEMS material for movement on a chip. The electrical circuit pulses cause the movement of the mechanical MEMS, which acts as an actuator for generating the ultrasound waves as well as the sensing of the much weaker echo signal for the medical imaging.

The project work may extend to any part of the system, depending on the background of the team members and composition of the team.

A device configuration for actuation and sensing could be selected from options in literature. It depends on the MEMS layer properties and layer thickness what voltage should be applied in order to generate a sufficiently large movement, for which the material properties have to be examined. Simulation of the device properties and technology layer composition of the supportive substrate and the electrodes on the PZT may make use of existing NXP device models and infrastructure. Options for the systems design are simulation at the level of the electrical pulse circuit for which a topology needs to be chosen, as well as the system level design in Simulink. The project team may possibly use an NXP internal satellite office in the device physics group in Nijmegen so that the team can work fully concentrated on the simulation tasks for two or more days per week. A phased approach in which some students do the preparing literature study first, followed by the device and systems simulations, is also an option, depending on the planning of the students. It should focus on the aim of the project, which concerns the PZT layer specifications for the deposition process of SolMateS.

A successfully completed design of the PZT device may result in the manufacturing of a test wafer by SolMateS for a continuation as a MSc project.

Supervisor            Dr. ir. J.J. Koning (Stan Ackermans Institute-DTI)
Supervisor            Dr. Eugenio Cantatore (Elect. Eng.)
Project duration     7 weeks (short internship)

Reageren / Contact

Koning, J.J.
040 - 247 5976
dr.ir. Cantatore, E.
040 - 247 3388