Optoelectronic Characterization and Modeling of Materials for Colloidal Quantum Dot Photodiodes

Solution-processable thin-film photodetectors are emerging as a key technology for short-wave infrared (SWIR) imaging in consumer electronics. These detectors enable devices to "see" beyond the visible spectrum, unlocking new capabilities in areas such as depth sensing, augmented reality, and virtual reality. Colloidal quantum dots (cQDs) based photodiodes, in particular, are a very promising candidate within this class and at the center of this project. Such a photodiode typically consists of a light-sensitive cQD layer, charge transport layers, and electrodes to collect the photogenerated current. Achieving high performance requires careful matching of the materials’ optical and electronic properties. Apart from the initial material selection itself, the fabrication method plays a crucial role in determining the final optical and electronic properties of the layers and directly impacts the device's overall performance.

In this project, you will investigate optical (how they interact with light) and electronic (how they conduct electricity) properties of different materials used in a cQD photodiode stack. You will also experiment with different ways of depositing these materials (e.g. evaporation, ALD, CVD), as the method used can significantly affect how the materials perform in a device. To evaluate your results, you will use a variety of characterization techniques (e.g., IV/CV measurement setups, ellipsometry, spectrometers). Based on your findings, you will build a model (e.g. Python, MATLAB) to compare materials and extract key performance parameters. Finally, you will use this model to simulate a complete photodiode stack with optimized device performance.

You will have the chance to learn about solution-processed cQD photodiodes and gain hands-on experience with different techniques for depositing/growing materials. You will also learn how to characterize materials using both optical and electronic measurement techniques. Your experimental work will be supported by data analysis and modeling, helping you draw meaningful conclusions from your results. In addition, you will have the opportunity to work in an international research environment, collaborating with experienced researchers and engineers who will support your scientific growth.

We are looking for a MSc student who is passionate about optoelectronic devices and has a basic understanding of semiconductor physics. You should be naturally curious and eager to explore new ideas. A background in nanoscience, nanotechnology, engineering, physics, materials science, chemistry, or a related field is important. Having a hands-on mindset and some initial programming experience (e.g., in Python or MATLAB) will be a big plus. Since you’ll be working in an international research environment, a strong command of English is essential for effective communication and collaboration.

Keywords

Material deposition/growth, electrical and optical characterization, data analysis, modeling/simulations

Type of work

Experimental work (60%), data analysis/simulation (40%)