Holst Centre Brings Spatial ALD to Flexible Electronics

Holst Centre, an open-innovation initiative by imec and TNO, is structurally embedding spatial atomic layer deposition (ALD) into its core technology portfolio in the flexible electronics domain. In keeping with its shared-research philosophy, Holst Centre is now actively looking for industrial and academic partners to join this new activity.

The aim is to develop the materials and processes needed to bring spatial ALD to market-readiness in new application domains such as organic photovoltaics (OPVs), OLED lighting and displays. The spatial ALD group builds on four years of expertise within TNO, which has already resulted in the creation of a spin-off company.

ALD is a technique capable of producing ultra-thin conformal films with atomic level control over thickness. It is widely accepted in, for example, the semiconductor industry. Recently a new field of applications interested in spatial ALD has emerged: flexible electronics. These include flexible displays, flexible OLEDs, and flexible (organic) solar cells. However, such applications require high-throughput and low-cost production techniques, often at atmospheric pressure, to make them economically viable. Pre-requisites that are considered to be weak points of (conventional) ALD.

Spatial ALD is an approach to reach these targets for high throughput and low cost. It’s an ALD mode where the reactions are separated spatially instead of through the use of purge steps. This allows high deposition rate and high throughput at atmospheric pressure, without compromising the typical ALD assets.

Dutch research organization TNO has already been active in the field of spatial ALD since 2008. The tool development has already led to the creation of a spin-off equipment manufacturer called SoLayTec. On the process side, one of the milestones has been the demonstration of Al2O3 layers with deposition rates compatible with high industrial throughput demands (10 – 100 times faster than conventional ALD).

“Spatial ALD can potentially benefit a substantial number of Holst Centre activities related to high-speed and high-precision material deposition on flexible substrates,” said Jaap Lombaers, managing director at Holst Centre. “We have great ambitions for this new activity, which in the short term will attract the interest of a number of new or existing industrial partners.”

For this new activity, Holst Centre sees many benefits for materials suppliers, equipment and component manufacturers and end users in the fields of flexible electronics, OLED lighting and displays, OPV, thin-film transistors, and more. A number of workshops have already been organized to detail the contents of the research roadmap in dialogue with (potential) partners. Holst Centre hopes to announce partnerships for the spatial ALD activity later this year.