Concept of the Nanoteg Project

The existing cooling techniques currently used for on-board avionics and aircraft equipment are not compatible with the heat flux foreseen (>50W/cm2) for the next generation of aircrafts. The problem is exacerbated when cooling is lost where the equipment should survive 30 minutes at 70°C. Thermal management issues were pointed out as the most critical challenge in designing compact and portable electronic devices. The International Technology Roadmap for Semiconductors (2007) indicated that the heat dissipation rate from a single chip package is expected to reach about 120 W for a cost-performance and up to 220 W for a high-performance single-chip packaging technology, respectively. It is generally agreed within the scientific community and equipment manufacturers that current air-cooling technologies are asymptotically approaching the limits imposed by available cooling area, available air flow rate, fan power and noise.

In the automotive industry,  power hungry devices are integrated on-board: the electrical loads of present automobiles are related to multimedia, heating, ventilation, and air conditioning (HVAC), body electronics (power windows and heated backlight) and lighting (exterior and interior) and their consumption is above 3 kW. A conventional vehicle with Internal Combustion Engine (ICE) part of the mechanical power (about 5 kW) to drive the mentioned on-board equipments through the alternator considering its efficiency of approximately 60%; an ICE vehicle is characterised by abundance of wasted heat (about 70% of total energy of the fuel) that is used to warm the inside during winter while a mechanical air-conditioner provides the climate control during summer with a power need of 2¸3 kW that causes considerable increase in fuel consumption, CO2 and pollutants emissions, weight and car complexity. On a Fully Electrical Vehicle (FEV), electrical auxiliaries are supplied by the batteries pack resulting in increased mass installed to guarantee reasonable covered ranges from 50 to 100 km; the power consumption of any kind of auxiliary contributes to reduce this range and to decrease the battery lifetime.

For all of these transport and industrial applications, specific solutions have to be identified and adopted to bring considerable advantages in terms of energy saving, costs reduction, architecture simplicity, people health and comfort.

Solid-state ThermoElectric (TE) devices have many attractive features compared with other cooling and power generation technologies such as no moving part and thus long lifetime, no emission of toxic gases, low maintenance and high reliability. TE materials are characterized by the figure-of-merit ZT that measures the energy conversion efficiency. While theoretical investigations reveal that there is no maximum ZT limit from physical standpoint, inexpensive and high efficiency TE devices would revolutionize the cooling industry, in particular in microelectronics to efficiently remove heat from circuits, thus improving lifetime and reliability of many electronic devices, such as CMOS-based microprocessors and semiconductors. In the other direction from heat to electricity, high ZT based TE devices could also tap the waste heat generated in engine combustion to make automobiles more energy efficient. Therefore, TE devices can make use of energy more efficiently and have a huge economic benefit as well as a societal benefit for the sustainable development.

The concept of the NanoTEG project is to solve crucial cooling and energy management issues in transport and energy efficient applications, based on the technical leverage enabled by highly efficient nanostructured TE modules compatible with high volume fabrication processes.

Thus in NanoTEG, we intend to produce relevant industrial demonstrators integrating innovative efficient cooling systems, creating a strong impact in two identified application domain: Automotive and Avionics.

Objectives of the Nanoteg project

This main objective will be enabled and supported by the development of two technical pillars, as illustrated in the above figure

  • nanostructured TE materials that are highly efficient (high ZT) and compatible with existing high volume fabrication processes;

To answer different end-user needs, several routes of applied research will be developed on nanostructured TE coolers combining different fabrication processes, all industry-scalable (sputtering, nanocomposite, printing), different materials (Bi2Te3, skutterudite, metal oxide) and different “nano-approaches” (superlattices and nanoinclusions)

  • innovative packaging and integration solutions, allowing the integration of the nano-TE materials into highly efficient modules (high CoP – Coefficient of Performance) at the core of the system-level demonstrators.

Innovative applied research on integration, packaging and interconnect technologies will be developed in order  to guarantee the high efficiency of the TE modules and ensure the short time to market implementation of the project results. Different packaging concepts (internal or external TEC integration), geometries, Thermal Interface Materials, underfilling and interconnect technologies will be developed in complete accordance to each demonstrator specifications.

Thus, the project consists in achieving the three major following objectives:

(i) develop highly efficient nanostructured TE materials compatible with existing high volume fabrication process,

(ii)  develop innovative packaging, interconnect and integration solutions to

(iii)  create a strong industrial impact by building four demonstrators integrating these technologies and solving, at system level, cooling and energy management issues for automotive and avionic applications.

The NANOTEG consortium (14 partners from 8 European ENIAC-member States) gathers all the competences required to achieve these objectives. It is well balanced and involves all the supply chain partners in order to anticipate the cost-effective introduction of these new technologies and future products on the market:

-    6 major European research institutes / universities addressing the fundamental scientific issues,

-    5 SMEs providing specific technological capabilities during the project and expecting short time-to-market benefits as return on investments in the exploitation phase;

-    3 major industries playing the role of end-users directly addressing the automotive and avionic applications.

The new market segments to be explored through the NANOTEG project are of capital interest for the European economical reinforcement.