ALD: The groundbreaking technology behind the last tech ‘NOBEL’

ALD: The groundbreaking technology behind the last tech ‘NOBEL’

David Ares, María Rízquez, Mato Knez and Mercedes Vila Juárez at CTECHnano facilities.

Finnish materials physicist Tuomo Suntola, who developed Atomic Layer Deposition (ALD) technology, has won Finland’s take on the Nobel science prizes.

ALD is a thin-film deposition technique with atomic scale precision growth. The process is based on the sequential release of precursor (chemical reactants) gas pulses to deposit a film in a layer-by-layer fashion. A first precursor is introduced into the process chamber producing a monolayer on the substrate surface. Afterwards, the chamber is purged with an inert carrier gas to remove unreacted precursor and reaction by-products, and a second precursor is pulsed into the chamber reacting with the first precursor to produce a monolayer of the desired film on the substrate surface. This process is based on two fundamental mechanisms: chemisorption saturation process and sequential surface chemical reaction.

ALD coatings provide excellent adhesion and low stress due to the chemisorption of precursors with the surface. The main advantages of ALD are the deposition of perfect films (pinhole-free), excellent repeatability, digital control of sandwiches, heterostructures, nanolaminates, mixed oxides, graded index layers, and doping. Furthermore, perfect 3D conformal coatings are developed with 100% step coverage: uniform coatings on flat, inside porous, and around particle samples.

ALD attracted semiconductor industries for making High-K dielectric materials based on the important advances that Tuomo Suntola proposed years ago, and it has been produced at an industrial level since the 70´s mainly in the semiconductor, LED´s and sensor industries. But, due to the advances in tool design and recipe development, the importance of ALD is now rapidly expanding for producing innovative nanoscale materials. Nowadays, new ALD applications are flourishing and they will be shortly part of our most common daily basis activities. Recent developments in nanotechnology and materials processing have brought the competitor thin film deposition techniques at their performance limits while new possibilities raised solely for ALD.

ALD novel potential applications are highly multidisciplinary.  It has an emerging potential on photovoltaic cells, flexible electronics, enhanced performance glass, paper and textiles, decorative coatings, new generation transistors and advanced energy materials technology.

Based on the idea of creating new materials by ALD for several applications other than microelectronics, CTECHnano was created. CTECHnano is SME located in San Sebastian-SPAIN, which provides thin-film coating solutions. This spin-off arises from an initiative of the leader of the nanoGUNE´s nanomaterials group, Professor Mato Knez, initial foundation of BIC Gipuzkoa and with the support of the nanoGUNE´s director, José María Pitarke. In addition to its business proposal, the innovation of CTECHnano also lies in the definition of its shareholding, which involve two Basque industrial companies (DIECAROS and CADINOX) and a public fund (BasqueFondo).

Experts in ALD technology, CTECHnano´s portfolio offers different products:
Development of innovative deposition processes, design and manufacturing of coating systems oriented to R&D and Industry, including industrial implementation viability, and standard coating services. Despite being still an spin-off, CTECHnano is already a reference in ALD all over the world. They have sold their machines in USA, China, Europe and they just started collaboration agreements with India and Japon. Moreover, it is the only Spanish company dedicated to the nanoscale coatings activity through ALD. They work for high European entities such as OSRAM Optoelectronics or the FNMT, but its scope of action is not only limited to the industry. There is also a close connection with the academic world, both research centres and universities. However, in this context, the ALD technique is not well established either. In fact, according to the CEO of the spin-off, Mercedes Vila Juárez, “ALD is not very exploited compared to other technologies such as PVD. And that benefits us” emphasizes. Besides, the variety of functionalities that ALD technology implies, allows it to be applied to completely different products, surfaces and sectors.

CTECHnano’s team believes that ALD will be part of the next disruptive innovations on technology and they want to encourage professionals working on material sciences and engineering, to include this innovative way of depositing materials in their research and development processes.