HiTUS Technology especially beneficial for...

PQL's HiTUS technology has proved to be especially beneficial for:

• High rate reactive deposition for dielectric material deposition - near ideal RI and electrical breakdown
• High rate deposition of magnetic materials using thick targets (up to 15mm thick at present)
• Stable stoichiometric film deposition from compound, alloyed or mixed material targets
• Low temperature deposition for plastic or other 'delicate' substrates.

Sputter Deposition Control with HiTUS

Once the plasma is generated in front of the target, in order to sputter material, a negative DC bias needs to be applied to the target. Without the DC bias no sputtering occurs.

The remote plasma generation in the HiTUS System offers a solution to the power constraints of magnetron sputtering, i.e. with the HiTUS System, above approximately 100V (after the initiation of sputtering) the target current saturates and there exists a pseudo-independence of target current and voltage, Fig 3.

Fig. 3

The RF power applied to the RF antennae determines the target current and the target voltage determines the sheath potential. The sheath potential determines the energy of the argon ions impacting the target surface, therefore the higher the target voltage, the higher the sheath potential, the higher the energy of the argon ions hitting the target which can in turn lead to increased target material removal and therefore higher deposition rate. Hence, working at constant RF power input but by altering the target voltage we are able to increase or decrease deposition rates without altering the plasma density.

Of course, by increasing both the target current and the target voltage, high deposition rates can be achieved and on this basis, naturally, by reducing both parameters very low deposition rates are achieved.

This is not possible with magnetron sputtering for very low deposition rates, as reducing the target voltage results in the plasma being extinguished.

The important bit is that for both high and low deposition rates the film properties remain the same.

To tune deposition rate is very interesting for some materials and in online multi-targets multi-layers production..

Indium Tin Oxide - Plasma Quest develops "World Leading" ITO Process on plastics

• 3.3Ω/□ sheet resistance achieved
• Typically 9Ω/□ with avg. transmission ~91.5%

• ρ <>

• ~ 90nm/min deposition rate
• 1.5cm bend radius with no losses
• Deposition onto planarised PET and PEN

Layers of ITO have been deposited onto planarised PEN substrates supplied by Dupont Teijin Films. Deposition rates of up to approximately 90 nm/min can be achieved using HiTUS technology. The films shown in the graph below have average visible transmissions (from 450 to 750 nm) of 89.7% and 91.6% with sheet resistance of 7 and 10 Ω/□ respectively. These measurements were made with the uncoated glass slide taken as the reference and hence represent the transmission of the coating alone.

A sheet resistance of 3.3 Ω/□ has also been achieved for films with a thickness of 1 μm corresponding to a specific resistivity of 3.3 x 10-4 Ωcm. These exhibited an average visible transmission of 87.0% from 450 to 750 nm. When curled up to approximately a 1.5cm bend radius, no significant change was noted in the sheet resistance across the entire sample.

Download PDF document

HiTUS - Thin Film Membrane Solution / Sputtering Solution

There are many technologies available to deposit the thin films required for membrane manufacture. One favoured route is to use PVD, and in particular magnetron sputtering. However, this technique is limited in its ability to meet the demands of complex current and next generation membranes. Additionally, it has many shortfalls that have been shown to be readily overcome using Plasma Quest’s HiTUS technology.

The stable high density plasma generated by HiTUS is done so independently of the target, which significantly opens up the sputter deposition parameter space. This enables ready tuning of the deposition parameters to optimise the thin film characteristics required of the membrane. Such optimisation enables very tight control of characteristics such as grain size, stress, density, stoichiometry and film thickness.

The following link shows a project on Palladium Membranes where the HiTUS technology is being applied in this field:

Palladium Membranes

Palladium Membranes

Plasma Quest are pleased to announce their intervention in a project for Palladium Membranes.
For further information in this project development or if you wish to make corporate contact on this matter, please contact Rémi Mollicone by email at remi@plasma-quest.com .

Information below:

PALLADIUM MEMBRANES

Hydrogen is used in many industry sectors and is one of the most important chemical commodities. It can be produced in several ways from water, hydrocarbons, alcohols and carbohydrates.

Palladium has a high hydrogen solubility, hydrogen permeability and hydrogen selectivity, and is thus a suitable material for hydrogen separation membranes. Some areas where Pd-alloy membranes for hydrogen separation and purification have technological relevance include:

* hydrogen production as fuel for fuel cells and combustion,
* for hydrogenation/dehydrogenation processes in the (petro)chemical industry, and
* hydrogen recovery and purification in various processes.

The main drawback of these membranes so far has been the high cost of the membrane material, which is strongly linked to the thickness (15–20 mm) of current commercial membranes. For broad use, it is therefore necessary to develop membranes with a reduced thickness of the Pd layer. In the last decade, a substantial research effort has been carried out to achieve higher fluxes by depositing thin layers of Pd or Pd alloys on porous supports, like ceramics or stainless steel. The most common methods to fabricate these composite membranes include electroless plating, chemical vapour deposition, physical vapour deposition and sputtering. In most cases, the thin Pd or Pd-alloy layer is prepared directly on the surface or inside the pores of the support.

It has been developed membranes of 1–5 mm thickness giving an increased cost-performance benefit, both due to the lower materials cost and the significantly higher flux obtained. Different from previous efforts we apply a two step process where the defect free Pd-alloy film is first prepared by sputtering deposition onto the extremely smooth surface of a silicon wafer. In a second step the film is removed from the wafer allowing the preparation of very thin membranes. These films may subsequently either be used self-supported or integrated with various supports of different pore size, geometry and size.

The flexible manufacturing method opens for applications ranging from micro-electromechanical system (MEMS) integration to large-scale power plants with CO2 capture. Calculation of cost and efficiency for Pd membrane technology used for transformation of methane/coal into H2/energy, compared to other post – and pre combustion CO2 free technologies, benefits the Pd technology.

Conclusions:

_ Thin Pd-Ag membranes (2 microns) have been manufactured using magnetron sputtering. The films have been applied on porous stainless steel tubes (PSS®). Multiple membranes of 50 cm have been prepared.

_ Membrane performance:

_ H2 flux up to 2477 mL·cm-2·min-1 at dP = 25 bar (400°C)

_ H2 permeances between 3·10-6 - 2·10-5 mol·m-2·s-1·Pa-1 in pure H2

_ Low pressure H2/N2 permselectivity > 7500

_ Maximum H2/N2 permselectivity at dP = 25 bar of 3000 (400°C)

_ H2 permeances up to 8·10-7 mol·m-2·s-1·Pa-1 in WGS so far…

_ A membrane life time of several (2-3) years (T _ 400°C) is assessed based on long-term stability tests over 250 days

_ Performance of the Pd-alloy membranes is higher than performance criteria for application in WGS-MR: promising alternative to be applied in power generation cycles with CO2 capture

PQL’s HiTUS technology makes a key contribution to this process. See:

http://www.plasma-quest.com/english.pdf & http://www.plasma-quest.com/hitusintroduction.pdf

Guide to HiTUS (10 Pages - PDF - Chinese) - 等离子体束溅射镀膜------一种新颖的镀膜技术

Plasma Quest have today published an additional guide to their HiTUS Technology. In addition to the English and French versions, a Chinese version can now be downloaded at 等离子体束溅射镀膜------一种新颖的镀膜技术 . It is a 10 page PDF file.

PQL at the Salon Vide (Vacuum) in Lyon, France

Plasma Quest were active participants at this year's Salon Vide (Vacuum) 2008 show in Lyon where the company's advanced thin film deposition technology was demonstrated to visitors.

Exhibition/Show website: http://www.vide.org/vide2008/uk/vide2008.html

Plasma Quest (PQL) at the Optical Complex Systems Conference at the Espace Miramar, Cannes

The PQL stand at the Espace Miramar during the OCS 2008 conference in Cannes. Rémi Mollicone (PQL International Business Development) is representing the company at the event covering Optical Complex Systems.

Plasma Quest at the OCS 2008 in Cannes - 17th March to 20th March

Rémi Mollicone from Plasma Quest will be present at the OCS 2008 fair in Cannes from the 17th to the 20th March 2008. Show takes place at the Espace Miramar where the Croisette in Cannes meets the Rue Pasteur.

This is the second annual event of the Optical Complex Systems fair.

Useful Links:
OCS2008 Flyer
OCS2008 Programme

Plasma Quest Ltd trial next generation Plasma Launch System (PLS)

Plasma Quest Ltd have significantly redesigned their Plasma Launch System (PLS) for use in sputter deposition production environments.

Key factors in the development of the new PLS were:-

• Low cost of ownership
• Reliable
• Easy Maintenance
• Compact design
• No moving parts
• Wide operating range
• Improved efficiency

The new design performed well during extensive proving trials here in the UK prior to being shipped to the USA where it will be installed on a customer’s production system.