Glow
Discharge, Etch, Film Thickness, and Sputter and Carbon Coating Attachments
EMS 100 Glow Discharge Unit
The EMS 100 is a simple, free-standing glow discharge system, typically used for hydrophobic to hydrophilic conversion of carbon coated TEM grids. The EMS 100 requires only a suitable rotary pump.
Freshly made carbon support films tend to have hydrophobic surfaces which inhibits the spreading of suspensions of particles in negative staining solutions. However, after Glow Discharge treatment with air, the carbon film is made hydrophilic and negatively charged, thus allowing easy spreading of aqueous suspensions. With subsequent magnesium acetate treatment the surface is made hydrophilic and positively charged.
In addition to Glow Discharge treatment using air, other process gases may be used to modify surface properties. For example, if alkylamine is used as a process gas, the carbon film surface will become hydrophilic and positively charged. On the other hand, using methanol as a process gas results in the surface becoming hydrophobic and negatively charged. Such treatments can facilitate the optional absorption of selected biomolecules.
Features
- Polarity of the head can be changed from positive to negative with respect to earth.
- H.T. vacuum interlock.
- Needle valve bleed control.
- Surface treatment and cleaning.
- Polycarbonate safety shield.
Glow Discharge Summary
| Atmosphere | Surface | Charge |
| Air | Hydrophilic | Negative |
| Air | Hydrophilic | Positive with subsequent Magnesium Acetate Treatment |
| Alkylamine | Hydrophobic | Positive |
| Methanol | Hydrophobic | Negative |
Surface Cleaning
In many instances, surfaces need to be completely cleared of contamination films or deposits. This applies particularly to EM components where such deposits impair the maintenance of a clean vacuum system. A Glow Discharge treatment can be used to clean such components ofundesirable residues.
D.C. Glow Discharge
In the DC+ Mode, the Glow Discharge system can draw up 1.5Kv. This allows high efficiency ion etching of the specimen surface to remove, for example, oxide or resist layers.
Glow Discharge
The Polarity of the Head can be switched from Positive to Negative with respect to Earth, for Carbon Film Surface Treatment or Surface Etching of Metallic Specimens.
Specifications
| Plasma Voltage | 0-1000V Variable DC @100mA |
| Electrode Polarity | +DC or -DC with Stainless Steel electrode (60mm Dia.) |
| Vacuum Chamber | 165mm (D) x 125mm (H) Glass |
| Instrument Case | 450mm (W) x 350mm (D) x 170mm (H) |
| Weight | 15Kg |
| Supply | 115V 60 Hz (6 Amp Max) 230V 50 Hz (3 Amp Max) |
Ordering Information
| 94000 | EMS 100 Glow Discharge Unit | POR | Request Quote |
| 94100 | EMS 100 Glow Discharge Unit for the EMS 450 & EMS 950 | POR | Request Quote |
| 91005 | RV-3 Rotary Vacuum Pump | $2,566.00 | Add to Cart |
EMS 125 Etch Facility Attachment
The EMS 125 consists of a Vacuum Collar, Stage with integral HT lead thró, and Shutter Assembly.
When configured as a Sputtering System, the "Target" material is biased negative with respect to earth, the whole of the chamber metal work also being bonded to earth.
During normal operation, the chamber atmosphere is rarified argon. A potential is applied between two electrodes. The argon molecules are ionized. Effectively, these molecules are now short of negative charge, and will therefore be attracted at speed towards the target. As these molecules strike the target material, they will dislodge parts of it. This material will then be attracted towards the specimen holder. Thus, any specimen placed on it will be coated.
When configured as an etch system, the target is now biased positive with respect to the specimen stage only. A shield is placed between the Stage and the Target simply to protect the target material.
FEATURES
- Etch and Sputter while maintaining vacuum.
- Vacuum Collar Assembly.
- Insulated Stage.
Ordering Information
| 91042 | EMS 125 Etch Facility (for the EMS 450, EMS 550 & EMS 650 Sputter Coaters) complete with Vacuum Collar and Glass Cylinder | POR | Request Quote |
Replacement Parts:
| 91043 | Spare Glass Cylinder | $175.00 | Add to Cart |
EMS 150 Film Thickness Monitor
The EMS 150 consists of a Control Unit external to the instrument and a Crystal Holder with an Interconnection Lead and Pre-Amplifier. In addition, it has a vacuum collar to suit the appropriate Instrument Chamber.
The quartz crystal is placed in the vacuum work chamber. One face of the crystal is exposed towards the deposition source, such that, as material is deposited it will coat the crystal. The crystal is connected via a vacuum feed through to external components, the whole becoming an oscillator whose output is controlled by the frequency of crystal oscillation. As material is deposited on the crystal, so its frequency of modification is modified.
This modification is used to determine the thickness of material deposited.
Features
- Terminate facility.
- Pre-selectable material density.
- Programmable tooling factor adjustment.
- Microprocessor controlled.
- Clean line design.
Applications
A variety of techniques are available for depositing thin films onto substrates - in EM these typically include sputter coating and evaporation of metals from a filament source. Accurate measurement and control of the thickness of such films is often critical in achieving the desired results. A Film Thickness Monitor (FTM) can be used to monitor and control the thickness of sputtered and evaporated metal films.
FTM as an option with bench-top evaporators
The EMS 150X module can be fitted to our high vacuum evaporators to monitor the metal evaporation or sputtering process and terminate it when the required thickness is reached. The quartz crystal holder and crystal are mounted in the vacuum chamber and connected to a free-standing monitor via a vacuum feed-through. NOTE: An integrated version of the EMS 150 is available for some of our coaters - please refer to individual product pages for details.
FTM and the measurement of carbon films
The EMS 150 can be used to measure the thickness of carbon films. However, carbon is a light element and due to the sensitivity
Specifications
| Instrument Case | 300mm (W) x 150mm (D) x 75mm (H) |
| Weight (Case & Collar) | 6Kg |
| To Suit: | EMS 450, EMS 550, EMS 575, EMS 650, EMS 675, EMS 950, and the EMS 975 |
| Crystal Holder | Exchange crystal facility |
| Density Range | 1.55 to 23.0g/cm-3 |
| Measurement Range | 5 to 999nm |
| Resolution for Carbon | 0.8nm |
| Resolution for Gold | 0.1nm |
| CMOS Memory Battery Back-up | 5 years |
| Supply | 115V 60 Hz (6 Amp Max) 230V 50 Hz (3 Amp Max) |
Ordering Information
| 91006 | EMS 150 Film Thickness Monitor complete with terminate unit including crystal holder and fitted crystal. Standalone. | POR | Request Quote |
| 91006-M | EMS 150 Film Thickness Monitor Built-in Module | POR | Request Quote |
Replacement Parts
| 91008 | Spare Crystals | (set of 3) | $250.00 | Add to Cart |
| 91009 | Spare Glass Cylinder | each | $175.00 | Add to Cart |
EMS 350 Sputtering and Glow Discharge Attachment
The EMS 350 system employs a Magnetron Target Assembly which enhances the efficiency of the sputtering process using low voltages, and giving a Fine Grain, Cool Sputtering, without the need to cool the target or the specimen stage.
Sputtering Attachment
The EMS 350 is a modular sputtering and flow discharge attachment. It allows surface modification to be carried out in a single unit without breaking vacuum. If fitted with a metal target, a range of non-pxidising metals, including gold (Au) and platinum (Pt), can be sputtered.
The EMS 350 accommodates a range of specimen stubs, which together with pre-selectable parameters, gives defined and repeatable film thickness depositions. The Instrument is fitted with 60mm diameter and 0.1mm thick gold quick change target, giving optimum consumable cost performance. The integrated instrument panel and plug-in electronics, maximize “up-time” and, with user friendly designs, ensures satisfactory multi-user discipline. The sputtering parameters of current and time can be pre-set. The sputtering head is interlocked with a vacuum switch mounted on the sputtering head in addition to the needle valve to control Argon Gas Flow.
Operating in DC+ mode, the EMS 350 can draw up 1kV, allowing surface modification (‘wetting’) of specimens such as TEM carbon support films. This allows surfaces to be cleaned of some contaminating residues.
The EMS 350 can also be converted to sputtering mode by the addition of a suitable sputter target.
Features
- Low energy ‘cool’ system– (2 watts for cycle of 2 minutes less than 2°C/minute temperature increase).
- Low voltage sputtering (Order of 100V means DC).
- High resolution fine coating (Order of 2nm Gold Grain).
- Precise reproducible coatings.
- Even thickness deposition (Typically 20 nm or 200 Angstroms for SEM work).
- Polycarbonate safety shield.
Hydrophilisation
Freshly-made TEM carbon support films tend to have hydrophobic surfaces, which inhibits the spreading of suspensions of particles in negative staining solutions. However, after glow discharge treatment with air, the carbon film is made hydrophilic and negatively charged, thus allowing easy spreading of aqueous suspensions. With subsequent magnesium acetate treatment the surface is made hydrophilic and positively charged. In addition to glow discharge treatment using air, other process gases may be used to modify surface properties. For example, if alkylamine is used as a process gas, the carbon film surface will become hydrophobic and positively charged. On the other hand, using methanol as a process gas results in the surface becoming hydrophobic and negatively charged. Such treatments can facilitate the optional absorption of selected biomolecules.
Polarity
The polarity of the head can be switched from positive to negative with respect to ground for TEM carbon film surface treatment (hydrophobic to hydrophilic conversion).
Glow Discharge Summary
| Atmosphere | Surface | Charge |
| Air | Hydrophilic | Negative |
| Air | Hydrophilic | Positive (with subsequent Magnesium Acetate treatment) |
| Alkylamine | Hydrophilic | Positive |
| Methanol | Hydrophilic | Negative |
Specifications
| Instrument Case | 450mm (W) x 350mm (D) x 175mm (H) |
| Weight | 10Kg |
| Sputter Heads | 165mm Dia. (to suit EMS 450, EMS 750, EMS 950) |
| Target | 60mm (Dia.) x 0.1mm (Thick) (Gold fitted as standard) |
| Deposition Range | 0-50mA |
| Deposition Rate | 0-25 nm/minute (see note *) |
| Sputter Timer | 0-4 minutes |
| Supply | 115V 60 Hz (6 Amp Max) 230V 50 Hz (3 Amp Max) |
| Services | Argon Nominal 4 psi |
* Note: When used with EMS 750 base instrument different parameters will apply.
EMS 750
| Target/Stage Spacing | 45mm |
| Deposition Rate | 25 nm/minute |
Ordering Information
| 91082 | EMS 350 Sputter Attachment complete with Target 60mm x thick (Gold fitted 0.1mm inclusive as standard.) | POR | Request Quote |
Replacement Targets
| 91010 | Gold target | $750.00 | Add to Cart |
| 91012 | Platinum target | $850.00 | Add to Cart |
