Radiation effects on CMOS LC oscillators
Last modification : Wednesday, July 21, 2021
The Advanced Integrated Sensing lab (ADVISE) is a research group at KU
Leuven Geel Campus performing leading-edge research on radiation tolerant ICs.
The group has achieved important scientific results in characterization of
advanced semiconductor components under radiation, modeling of radiation
effects in circuit simulators and has presented several radiation hardened
mixed-signal and analog integrated circuits. ADVISE has its own RELY lab which
allows electrical characterization and radiation experiments concerning total
dose effects and single event upsets. The research group has gained world-
leading expertise in the design of radiation tolerant time-based circuits and
is a member of the CMS collaboration at CERN.
Oscillators are the main buildingblocks for frequency generation and are
widely used in communication systems, FPGAs and time-accurate systems. In
application such as spacecrafts and satellites, high-energy physics
experiments like those installed on the HL-LHC(High-Luminosity Large Hadron
Collider) and Future Circular Collider (FCC) and nuclear instrumentation
such as in the ITER (International Thermonuclear Experimental Reactor)
fusion reactor, large amounts of ionizing radiation can cause sudden phase and
frequency errors in the oscillator due to chargesdeposited by the particles.
Fortunately, advancements have been made in the reliability of PLLs over the
past 30 years and major improvements were achieved when migrating towards All-
Digital PLLs (ADPLL) in which the feedback loop is implemented entirely
digitally by replacing sensitive analog blocks (such as charge pumps) with
redundant digital filters. Henceforth, the critical circuit remains the
oscillator which still operates in analog mode.
Single Event Effects (SEEs) have usually been considered a result of charge
collection in the source/drain junctions of a MOS transistor giving rise to
Single-Event Phase Transients in the oscillator. Recently, we have made a
ground breaking discovery of a secondary and furthermore dominant mechanism LC
oscillators which is caused by electron and hole pairs generated in the oxides
(SiO2)surrounding the spiral inductor that cause Single-Event Frequency
Transients (SEFT). Although inductors are passive structures, their
electromagnetic behavior (parasitic capacitance) can be impacted by free
charges inside and around its geometry. The main goal of the project is to
understand this mechanism and develop techniques to reduce the impact on LC
Throughout your research, you will have the opportunity to develop and test
several chips to prove your developments in practice.
A master degree in Electrical Engineering or equivalent (Cum Laude).
A background in one of the following fields: CMOS Integrated Circuits,
Electromagnetic Fields, Radiation Effects on Electronics.
A curious mindset and motivation to tackle state-of-the-art research
The goal to become a top researcher in the field.
Note: We cannot take applications from nationals of the following countries
due to access restrictions imposed by the chip foundry: Cuba, Iran, North
Korea, Syria, Sudan, Irak, Pakistan
We provide you:
A 4 year funded PhD at KU Leuven.
A place in a world leading research group with state-of-the-art
The ability to work independently on your research.
Daily supervision and input for your research and technical assistance to
The possibility to design, manufacture and test several nanoscale ASICs.
The opportunity to work with leading institutes like CERN, IMEC and ESA
(European Space Agency).
For more information please contact Prof. dr. Jeffrey Prinzie, mail:
email@example.com or Prof. dr. ir. Paul Leroux, mail:
KU Leuven seeks to foster an environment where all talents can flourish,
regardless of gender, age, cultural background, nationality or impairments. If
you have any questions relating to accessibility or support, please contact us