ADVANCED COATING TECHNOLOGY

SVOTek specializes in the design, manufacture and production of precision optical components. Starting with customer’s drawing and specifications, we deliver high-quality and fully tested products to meet your requirements. We work closely with our customer from single-piece development all the way to high-volume production. See the following information on our capabilities in each department. Contact our sales team to find out more about our capabilities.

ADVANCED COATING TECHNOLOGY

SVOTek understands each coating technology has its unique advantages and limitations. In order to provide our customer the best service, SVO chooses amongst these in-house coating technologies, using each one's specific capabilities to deliver the best combination of performance, physical characteristics and cost savings to meet our customer needs.

• Ion Beam Sputtering (IBS)

In IBS, a high energy ion beam bombards a target. The ions transfer their momentum to the target material, causing atoms or molecules to be forced off (sputter) the target. These high energy particles deposit onto the parts.

Advantages:

1. High energy of the ion beam sputtering process results in extremely uniform and high density films with the best adhesion to the substrate.
2. High environmental stability and mechanical durability.
3. Surface roughness of the deposited layers is very low.
4. Low scattering and absorption
5. Easy and accurate process control
6. High reproducibility
7. Create high damage threshold films

Disadvantages:

1. Relative High cost, cost per unit coating
2. Filter size is limited
3. Not for deep UV or far IR

Best Choise for following Applications:

1. High power laser
2. Broad Band filters
3. Sharp edge filters
4. Filters used in tough environments

SVOTek is equipped with four IBS chambers with crystal and optical monitoring system. We provide high quality coating to meet our customer’s most stringent requirement. Oxygen is used in the coating chamber as a reactant to either create oxides when using metal targets, or to re-oxidize any free atoms dissociated by the sputtering process when using oxide targets.

• E-beam with advanced Plasma

Electron-beam deposition is the most commonly used coating technology. It’s also the least expensive one. An electron beam is generated from a hot filament focused through a magnetic field into a copper crucible. The crucible is filled with the material to be evaporated. The electron beam heats the material causing it to evaporate onto the substrates circling above it.

Advantages:

1. Low cost
2. Works with coating materials from the deep UV through the Far infrared

Disadvantages:

1. Heat cycling during processing can limit substrate choice and introduce internal stress
2. Lower environmental stability and mechanical durability

For even more capability, SVOtek has five E-beam with APS(Advanced Plasma System; explain this too) coating machines to produce larger quantities, FIR and many other different applications.

• Ion Assisted Deposition (IAD)

IAD is a variant of the electron-beam evaporation process which adds a high energy ion beam that is directed at the part to be coated. These ions act almost like an atomic-sized hammer, producing a higher film density than can be achieved by evaporation alone. The ion beam can also be used to pre-clean or etch the surface of the substrate, which improves film adhesion.

The advantages of coatings with this higher density are improved mechanical durability, greater environmental stability and lower scatter. The intrinsic stress of the individual layers of an overall coating is determined during deposition, which can vary from tensile stress to compressive stress.Balancing these stresses maintains the substrate’s surface figure. This is especially important when depositing thicker infrared coatings. This balancing of the coating’s stresses also extends the overall wavelength range over which the process can be utilized.

For example, while IAD is not compatible with some of the commonly used materials in the infrared, it can be used solely on the outermost layer to yield an overall coating with superior durability.

Advantages:

1. Enhanced density provides good compromise between cost, spectral stability and durability
2. Can be used from the UV through the IR
3. Material choices can be broadened because heating of the substrate is (or can be ) avoided

Disadvantages:

1. Higher scatter and loss than IBS

• In-line Magnetron sputtering

SVOTek is not limited to batch coating either. We have an in-line magnetron sputtering coater for metal, ITO-, semiconductor and solar cell coatings. Our Leybold system allows us to compete with other thin film coating providers and to offer significant price discounts. These savings are due to the in-line nature of the systems’ configuration. As the system has modular chambers (multiple) which are internally connected except for the input and output on either end, it is a continuous operation; as you load one substrate sheet in the input side, you are taking a coated substrate out the output side. Also because of the free flow of substrates between these modules, the parts are shuttled between chambers for specific layers to build the coating ‘stack’. In the present configuration, the maximum substrate size is 400mm x 450mm. The high throughput of the in-line magnetron sputtering allow SVOTek to pass on the saving to its customer. Our current set-up has 3 metal targets, but we can add more modular chambers, if needed, to meet increasingly complex coating designs.

Advantages:

1. Cost effective
2. Clean
3. Lower chances for defect.
4. Primarily for Volume production.

Disadvantages:

1. Size Limitation
2. Cannot coat curve parts due to chamber's geometry
3. Uniformity can only be 1%;again, due to the geometry of the chambers' anode/cathode

Best for following Application:

• Metal films (mirrors and reflectors), functional film (sensors and Nitride films) protection films (scratch prevention and oxidation prevention), solar cell films and decorative application.