PhD position - Modelling and optimization of Ge on Si Separated Absorption Single Photon Avalanche Diodes

OPPORTUNITY DETAILS

Total reward

0 $

State University

CEA Tech

Area

Western Europe

Host Country

France

Deadline

31 Oct 2021

Study level

Doctoral Degree

Opportunity type

PhD

Specialities

Physics , Chemistry

Opportunity funding

Not funding

Eligible Countries

This opportunity is destined for all countries

Eligible Region

All Regions

SL-DRT-21-0477

RESEARCH FIELD

Photonics, Imaging and displays

ABSTRACT

Advanced optoelectronic devices such as the single-photon avalanche diode (SPAD) are now widely employed in the fields of 3D imaging, camera assist, laser ranging and proximity. Next generation of SPAD will be devoted to time-of-flight 3D ranging and fast movement detection, notably for long LiDaR used in autonomous driving cars. The PhD work will consist in developing and exploiting home-made simulators for optoelectronic devices and more specifically, Ge separated absorption SPAD. In this type of sensors infrared light is absorbed in germanium and photogenerated carriers are transported into the silicon avalanche zone for signal amplification. A close understanding of the transport between the two materials is fundamental for optimization of the device. This will be done through simulation and calibrations of the models.First, process simulations of doping implantation, but also residual strain in the epitaxial Ge layer will be used to extract realistic doping profiles and hence inserted in the Monte Carlo (MC) code.Second, by using 3D particle MC simulation for solving the Boltzmann transport equation, the time behavior of different designs of Si- and Ge-based SPAD devices will be statistically analyzed in order to reduce the jitter and to enhance the photon detection probability. The MC technique is a unique tool to analyze single particle trajectories as well as the time evolution of terminal currents and voltages.