Project description

In the Large-Area Thin-film Transistor Electronics (LATTE) group of imec, we design the newest generation of circuits using thin-film transistors (TFT) [1-6]. The transistor channel in these devices can be made of low-temperature polycrystalline silicon (LTPS) or Indium-Gallium-Zinc Oxide (IGZO), which is deposited on flexible substrates, allowing us to make flexible circuits. We have two different versions of flexible 8-bit 6502 microprocessor circuits: LTPS and IGZO [1, 2]. Further characterization of the existing circuits is needed to evaluate and compare the technologies, testing methodologies and to improve the design of the next generation digital circuits.

Project objectives

In this internship you will characterize flexible microprocessor chips and analyse their performance under different conditions. You will evaluate the functionality and performance of the chips, such as speed, power consumption, lifetime, flexibility… If required, you will be involved in improving the test setup by designing new printed circuit boards. Depending on the length of the internship, we will then investigate the design of the next generation of circuits. If time allows, we also want to share the results in a publication.

Project tasks

As the intern, you will follow these steps:

• Read up on the specifics of the IGZO and LTPS technologies and digital circuit design
• Measure basic digital circuits with available lab equipment
• Compile Python scripts to interact with equipment efficiently and plot results
• Program the microprocessors using Assembly language
• Program the FPGA using Verilog language for testing the microprocessors efficiently
• Optional: design a new PCB for improving the measurement setup
• Optional: use the learnings to design the next iteration of the microprocessor
• Optional: write a research paper on the findings

Requirements

To bring this project to a satisfying conclusion, you will need the following things:

• A background in circuit design
• Preferably enrolled in a circuit design master or adjacent
• Enjoy getting your hands “dirty” in the lab
• Strong communication skills
• Lots of positive energy and initiative
• The desire to be part of an enthusiastic and supportive team

Depending on the time available this internship can be anywhere from 3 to 9 months.

Further reading

[1] Multi-project wafers for flexible thin-film electronics by independent foundries

https://doi.org/10.1038/s41586-024-07306-2

[2] Flex6502: A Flexible 8b Microprocessor in 0.8µm Metal-Oxide TFT Technology

https://doi.org/10.1109/ISSCC42614.2022.9731790

[3] Multimodal Intelligent Display Backplane Blocks

https://doi.org/10.1002/sdtp.17894

[4] Flexible TFT Read-Out Circuit Blocks for Large Area Sensor Array System Integration

https://doi.org/10.1109/JFLEX.2024.3433322

[5] A Novel 2T Pixel Topology Enabling High-Quality Optical Fingerprints

https://doi.org/10.1109/JFLEX.2023.3302827

[6] Multiplexed Surface Electrode Arrays Based on Metal Oxide Thin-Film Electronics for High-Resolution Cortical Mapping

https://doi.org/10.1002/advs.202308507