ionbeam scientific logo ionbeam scientific header

 Ion beam applications

An ion source is an extremely versatile process aid to a thin film deposition system. Unlike conventional higher-pressure glow discharge and plasma processes, which suffer from plasma spread, the ion source provides a confined and directed plasma to the substrate or sputter target, at low pressure, with controlled ion current and energy. How could this help you?

Ion beam pre-cleaning (IBPC)

Ion Beam Pre Cleaning

In-situ substrate pre-cleaning can therefore be carried out at low pressure immediately prior to deposition, and very rapidly and effectively removes native oxide films and any substrate surface contaminants which would otherwise effect the initial film nucleation and adhesion.

As the ion source operational pressure range is compatible with electron beam evaporation, or magnetron sputtering, the deposition process may be ‘phased in’ without halting the ion beam cleaning process, hence providing a resultant improvement in film adhesion.

Tests have shown that using this technique, thin film adhesion to the substrate can improve by up to a factor of seven. Unlike glow-discharge cleaning, the plasma is confined purely to the substrate area. Any contaminants are ejected away at normal incidence from the substrate surface, and hence the risk of a non localised plasma striking the process chamber walls and fixturing releasing further contaminants, is eliminated.

 See our technical article for more about ion beam pre-cleaning

Ion beam assisted deposition (IBAD)

Ion Beam Assisted Deposition

Additionally, the source can be operated during the deposition process, whether this to be thermal, e-beam or magnetron deposition, to provide beneficial effects in thin film nucleation and packing density to produce void-free thin films.

In many instances, the need for substrate heating can be eliminated, or process temperatures can be significantly reduced, permitting coatings on delicate substrates such as plastics and also reducing system cycle time. Gases such as oxygen or nitrogen may also be used to assist in the formation of oxide or nitride films or to eliminate the effects of depletion.

 See our technical article for more about ion beam assisted deposition (IBAD)

Ophthalmic coating

Ophthalmic coating

Not surprisingly, the ion source has found much favour in the ophthalmic coating industry. It is also common for users to report that they consider the ion source to be of equal process importance to the e-beam evaporation source installed in their deposition systems.

While it is primarily used as a means of in-situ pre-cleaning, particularly on plastic lenses which have low heat tolerance, it can also be used with oxygen to assist the deposition of oxide films. And to produce harder coatings. Typically, the end-hall gridless ion source is ideal for this type of application.

Ion beam milling (IBE)

ion beam milling

Ion beam milling provides a means of a controlled directional etching process on both metal and dielectric materials. This enables highly anisotropic etching to be achieved on sub micron geometries with defined etch wall angles. An additional advantage is that the ion beam energy may be controlled to minimise damage of sensitive substrates.

Both inert or reactive gas ion species may be used, in the latter case, this provides chemical assistance to the physical material removal process and is known as Reactive Ion Beam Etching (RIBE) or Chemically Assisted Ion Beam Etching (CAIBE).

Ion beam sputter deposition (IBSD)

Ion beam sputterdeposition

Ion beam sputtering is a means of depositing thin films of exceptionally high quality and possessing very fine structured thin film characteristics. A wide range of metal and dielectric materials can be deposited. The deposition process is carried out at much lower pressures than conventional magnetron sputtering. It is also a cooler process as substrates are not exposed to the plasma. Sputter target utilisation is also far superior.

Although not a very high deposition rate production process, the resultant film properties achieved in terms of adhesion, density and structure are far superior when compared to other sputtering or deposition techniques. Reactive gases can also be introduced through the ion source to provide even more deposition process flexibility (RIBSD).

Direct ion beam deposition (DD)

Direct ion beam deposition

Direct ion beam deposition may be achieved when typically a hydrocarbon gas (or mix of gases) is fed through the ion source. This results in the gas ‘cracking’ resulting in the formation of a carbonaceous film forming directly on the substrate.

This process is often utilised to deposit Diamond-Like carbon films (DLC) with wide ranging applications, and also wherever very hard abrasion resistant coatings with specific tribological properties may be required.

 Have a question? Please contact us for help