Finnish coating technology specialist Picodeon has developed a technique for depositing diamond-like films onto a wide range of substrates using its patented ultra-short pulsed laser deposition (US PLD) technology.

Diamond-like coatings create super-hard surfaces (greater than 40 Gpa) with a low coefficient of friction and excellent coating adhesion. The US PLD deposition process uses a high laser pulse repetition rate and fan-shaped plasma bloom, which enables high production rates and makes the industrial coating of large surfaces at film thicknesses down to nano-scale feasible. Pulse duration is in the range of picoseconds, typically < 10 picoseconds.

The substrate is cleaned prior to coating to remove dirt and moisture. Typically, pre-cleaning takes place in a separate chamber prior to transfer to the deposition chamber. For some materials, the substrate is preheated to temperatures up to 800-950 °C to promote the formation of a suitable surface structure.

Applications for diamond-like coatings range from machine tooling components to wear components for medical, optical and sensor applications.

“Any components that need to have the highest possible hardness or wear resistance can achieve improved lifecycles, greater heat and pressure resistance and/or improved performance with diamond-like coatings,” said former Picodeon CEO Marko Mylläri. “Our US PLD deposition process can deliver the exact surface defined by our customers’ engineers because of the high level of tuning enabled by our process.”

Picodeon’s US PLD deposition is a cold ablation technology that works across a vast range of coating materials and substrates. By adjusting processing parameters, the structure and properties of the coating can be tailored to the requirements of the application, even for nanostructure-scale surface coatings.

In principle, any type of substrate can be used including metallic, ceramic, composite and elastomer due to the low heat effect on the substrate. Naturally, there are preferred substrates that are used for certain substrates e.g. for hard tribological coatings with high surface pressures. The hardness of the substrate should be sufficient to support a thin (max. 2.3µm) coating.

The US PLD technology delivers very high coating integrity without pinholes, giving improved reliability in applications where through-thickness defects may cause delamination of thin films and serious damage to components. In addition to diamond-like coatings, US PLD technology, under the trade name Coldab®, enables the deposition of carbon nitrides, carbon nitride composites containing PTFE or boron nitride (BN) as well as a wide range of other borides, oxides and precious-metal thin films.

The high production rates and excellent coating qualities of Picodeon Coldab US PLD technology opens new possibilities and applications for pulsed laser deposition coatings. In selected areas, it may even enable the development of exclusive coating methods.

 Picodeon is a nanotechnology company specializing in thin film coatings and surface treatments with its patented Coldab Ultra-Short Pulsed Laser Deposition (USPLD) process. The company is located in Ii, northern Finland, and provides equipment, solutions and services for clients worldwide.