Postdoctoral Researcher Reliability of Thin-film IGZO Transistors for Logic and Memory Applications
What you will do
In the last decade, oxide semiconductors have emerged as a higher performance replacement for standard amorphous silicon thin-film transistors (TFT's) in display back-plane applications. Among different material candidates, Indium-Gallium-Zinc Oxide (IGZO) is the most promising, providing high performance with large area uniformity, low off-currents and low-temperature processing. As a result of the exceptional electrical characteristics of this material, it is envisaged to use it in new areas such as power gating and access transistors in DRAMs.
The exponential increase in leakage power due to technology scaling, has made power gating an attractive solution for ultra-scaled CMOS technologies. Power gating switches are typically formed in a front end-of-line (FEOL) portion of the Integrated Circuit (IC). However, these switches occupy valuable substrate footprint, which results in added die size of the IC device. Furthermore, a power gating switch formed in the FEOL portion is accompanied by long current paths from the access pins of an IC to the power network of a gated portion on the chip, which can lead to significant power losses. Thus, there is a need for IC devices in which power gating switches are formed in a back end-of-the line (BEOL). These BEOL switches must be based on a high-performance device while being fabricated on a low temperature budget to preserve the functionality of the FEOL devices and interconnects. IGZO is the prime candidate to be used for BEOL power gates.
Dynamic random-access memories (DRAMs) are one of the indispensable electronic components. The advantages of the DRAM are large memory capacity, high-speed operation and low price per bit. The disadvantage of the DRAM is the need for constant refresh. In this regard, a selector transistor that has an extremely low standby leakage current would allow the refresh cycle of DRAM to be very long or, for a practical use, to be non-existent. Refresh-free DRAM would be the ultimate memory. Due to the extremely low off-current of IGZO TFT's used as access transistors, such universal memory could become reality.
However, long-term reliability of IGZO devices is one of the most important aspects to be still fully characterized and understood before full deployment. The aim of this work is hence to study the overall IGZO TFT reliability, targeting both logic and memory applications. To this end, this novel device must be fully characterized and modelled, from which fundamental understanding and possible reliability limitations are extracted, allowing for further process optimization and eventually the employment of these devices in real products.
What we do for you
We offer you the opportunity to join one of the world’s premier research centers in nanotechnology at its headquarters in Leuven, Belgium. With your talent, passion and expertise, you’ll become part of a team that makes the impossible possible. Together, we shape the technology that will determine the society of tomorrow.
We are proud of our open, multicultural, and informal working environment with ample possibilities to take initiative and show responsibility. We commit to supporting and guiding you in this process; not only with words but also with tangible actions. Through imec.academy, 'our corporate university', we actively invest in your development to further your technical and personal growth.
We are aware that your valuable contribution makes imec a top player in its field. Your energy and commitment are therefore appreciated by means of a competitive salary.
Who you are
- You have a PhD in Microelectronics, Material Science or Physics
- We are looking for your experience in physical modelling
- We value your experience in electrical characterization
- You have a solid background in reliability physics and scripting languages (Python) for analysis of large data sets
- You are a constructive team player and actively share experience and knowledge with colleagues.
- We are looking for your excellent communication skills in English, as you will work in a multicultural team
This postdoctoral position is funded by imec through KU Leuven. Because of the specific financing statute which targets international mobility for postdocs, only candidates who did not stay or work/study in Belgium for more than 24 months in the past 3 years can be considered for the position (short stays such as holiday, participation in conferences, etc. are not taken into account).