ARCES Research Projects started in 2012:

1 - Novel device and circuit concepts for energy-efficient electronics (FIRB)

2 - GRC Research 2257 “Modeling of Package Influences on High-voltage semiconductor FETs”  (SRC)

3 - E2SG - Energy to Smart Grid (ENIAC-JTI)

1 - Novel device and circuit concepts for energy-efficient electronics

The aim of this project is to reduce power dissipation in electronic devices without reducing, or even improving, the performances. The development of a device that can operate at sub-0.5V is going to have a great impact on future digital circuits, and is likely to generate new circuit architectures, which can take full advantage of this new device. The successful deployment of a novel device is made possible by technological advances as well as by circuit models allowing circuit designers to actually use these devices and create new circuit architectures. This is why this project targets the development of appropriate models and simulators to accurately describe the device performance. Also, the development of computational tools is expected to have significant impact on understanding of these devices and on the ability to predict the performance and optimization criteria for individual devices as well as circuits.

The project proposes to analyze two novel device concepts that can provide a much more abrupt transition than the 60mV/decade limit of MOSFETs at room temperature, hence reducing the subthreshold leakage and lowering the operation voltage. This goal can been pursued by filtering out high-energy electrons injected into the channel.

The project focuses on two different ways to realize this filtering function: (i) the Tunnel-FET (T-FET) where the thermionic emission of charge carriers over a barrier is replaced by a band-to-band tunneling process and, (ii) the superlattice FET (SL-FET), where the filtering function of high energy electrons is entrusted to a superlattice interposed between the source and the channel of a nanowire FET. This beyond-CMOS device concept will be further advanced by the use of nanowire structures and the introduction of non-Si materials (SiGe, Ge and III-Vs) integrated on a silicon platform.

This project is financed by Italian Ministry of Education, University and Research through the call “Futuro in Ricerca 2010” and it includes three Universities with a very strong and world-wide recognized expertise in the modeling and characterization of advanced semiconductor devices, namely the University of Bologna, Udine and Padova. It also takes advantage of the collaboration with CEA-LETI Grenoble, IBM Zurich and the University of California at Santa Barbara. ARCES is Coordinator of the project for the University of Bologna, with the researcher Prof. Elena Gnani as Principal Investigator.

2 - GRC Research 2257 “Modeling of Package Influences on High-voltage semiconductor FETs”

This project is focused on the study of reliability and performance of high-voltage (200-10kV) IC technologies influenced by packaging materials and designs. Among others, the effect of ionic contents and conductivity, charge creep and polarization will be studied with respect to the specifications and properties of mold compound, buffer layers, fillers, die attaches and other packaging materials.

The high-voltage stability of Silicon, SiC and GaN HV FETs and high-voltage galvanic isolation integrated components will be compared under typical packaging layers, within relevant electric field, temperature and stress ranges. The influence of HV biasing on surface parasitics shall be related to the layout of HV sources. The effect of HV within MCM packages is also to be addressed. The different designs and models will be simulated in a commercial device TCAD tool. Custom models may be investigated in separate analytical and/or numerical studies.

The expected outcome of the project is a set of models and testing methodologies for the description, identification and avoidance of coupling effects between package and high-voltage semiconductor dies. The study, mostly numerical but verified by measurements whenever possible, is expected to cover different die technologies and layouts, packaging material properties, single die packages and Multi-Chip-Modules.

The project, which started on February 1st 2012, is financed by Semiconductor Research Corporation and the Principal Investigator is ARCES researcher Prof. Susanna Reggiani.

3 - E2SG - Energy to Smart Grid

The target of E2SG project is to devise and design mechanisms and policies to assemble, monitor and control smart grids, i.e. a set of interconnected nodes whose primary goal is to generate, exchange and consume electrical energy in the most efficient and reliable way by exploiting distributed information that is sensed, transmitted and processed over the same set of nodes and links. From this point of view, E2SG is complementary with respect to another ENIAC project started in 2011, ERG (Energy for a green society), that focuses on nodes with generation abilities whose interfaces are the main topic of common interest between the two projects.
E2SG aims at addressing most of the challenges entailed in evolving the concept of smart-grid to the level needed by both the industrial players and the society of the next decades, and the uprising environmental awareness which will lead to the increasing exploitation of removable energy sources.

To do so, E2SG aims at developing and demonstrating key enabling technologies, at least in the following fields:
1. node-grid interfaces, especially between generating nodes and the grid;
2. grid-sensing/metering, to collect the information needed for management and control;
3. over-the-grid communication, to effectively carry sensing and control information where it is needed;
4. grid-topology and control, to understand and design connection-induced behaviours improving reliability and to control (local) energy production/distribution by exploiting advanced storage policies;
5. energy routing, to develop flexible and efficient mechanism to transmit energy between nodes, e.g. by properly choosing AC or DC links depending on temporary operating conditions for power consumption.

E2SG is coordinated by INFINEON (Germany) for the overall european project, while the Italian lead-partner is ST-Microelectronics.