Interface Materials / Phase Change Materials
The increase in the complexity of technical devices, modules or even individual components is the focus of the aspects of reliability, durability and thus the costs of exchange and revision work. Especially in the focus here is of course the power density in power electronic components which has steadily been increasing for years; A direct and decisive influence on the entire service life of semiconductor components is therefore more than ever the effective cooling, because the heat flux as a measure for the dissipated heat per area unit is usually the critical value at the macro level and responsible for the resilience of the application.
In fact, materials are often used for this, which do not always correspond to the application and do not always meet the increasing requirements. So-called phase changing heat conducting interface materials offer the optimal solution here. These thin film coating-based metal substrate carriers are ideally suited for the cooling of power semiconductors in modular design and high-power LEDs.
Of pure interface materials is usually spoken whenever substrate layer thicknesses of less than 0.20 mm can be used in the application.
ICT SUEDWERK's heat-conducting phase-change materials wetting the unavoidable surface roughnesss during softness above the phase change temperature, and expel air pockets from the micro pores of the surface. Due to the fact that type-dependent phase change materials extend with increasing temperature volumetric, the wetting of the contact surfaces is additionally improved.
Due to the liquefaction and expansion as well as the capillary effect, so-called air pockets between the thermally contacting interface are expelled or pressed out. The first overrun of the phase change temperature is sufficient and a permanent thermal contact is established, which is then kept constant over and under the phase change temperature. Due to the full-surface wetting, the thermal connection to the conventional is therefore superior to variants and the resulting thermal resistance is significantly lower. The different phase change materials can also be ordered in several different variants:
- As standard variant aluminium and copper substrate carrier in phase change coating
- As a phase change variant with graphite particles/fibres, which is electrically conductive and also reduces the thermal transition resistance
- As a pure phase change Compoundfilm which is offset by high heat conductive particles and thus a thermal conductivity of up to 3.5 W/mK is achieved
- As a pure compound in cartridge or block format or as a so-called fill-up stick (dispenser)
Phase-Change How does this process work?
When the temperature approaches the defined phase change point, the material changes its aggregate state and passes from the solid, dry to the soft to liquid state. Unavoidable surface roughness are balanced, air pockets are expelled from the micro pores of the surface. In addition, the fact that phase change materials expand volumetric when the temperature increases, the wetting of the contact surfaces is additionally improved. Convex and concave unevenness of the contact surfaces and tolerances can thus be mastered very well.
| Properties | Unit | ICT-Ap60-Series | ICT-Ip50- und 60 Serie | ICT-PC-Fillup-STICK | ICT-Xp45-Serie- |
|---|---|---|---|---|---|
| μm | 51 | 51 | - | - | |
| Phase-change material | - | Silicone-free paraffine wax | Silicone-free paraffine wax | silicone free paraffine compound | pure film interface compound |
| Color | - | Weiß | white | Black|Schwarz | white and black (Graphite) | grau/Grey |
| Material gauge with coating (µ) | µm | 76 | 100 | 151 | 76 | 84 | 114 | - | - |
| Layer thickness of wax coating | µm | 12,50 | 25 | 51 | 12,50 |16,50 | 31,50 | - | - |
| Thermal conductivity | W/m*K | 220,00 | 220,00 | 0,47 to 3 | 3,50 |
| Thermal resistance (inch² / 645,16mm²) | K/W | 0,03 | 0,052 | 0,060 | 0,03 | 0,007 | 0,02 | 0,07 |
| Phase-change temperature | °C | 50 | 60 | 50 | 60°C | 51 to 60 | 45 °C |
| Operating temperature | °C | from -40 °C to 140 °C | from -40 °C to 140 °C | from -60 °C to 140 °C | from -40 °C to 140 °C |
| Storage temperature (max) | °C | 35 | 40 | 18 to max 40 | 35 |
| Filler | - | - | Graphite particles | - | - |
| UL flammability rating | UL | - | -- | - | - |
| Material | Aufbau | - | - | PCM Interface compound | pure film | compound |
| Other | - | - | - | ICT-FILLup-STICK | - |
| Material gauge (µ) | µm | - | - | - | 100 | 200 | 300 |
| Gauge tolerance (µ) | % | - | - | - | 10% |
| Thermal conductivity through-plane (z-direction) ASTM | Wm/K | - | - | - | 1,67 λeff [W/mK] |
| Thermal resistance (inch² / 645,16mm²) | K/W | - | - | - | 0,03 ASTM D 5470-12 |
- The thermal conductivity of all ICT-phase-change-film and pure compound film types is excellent, as is the thermal resistance, which can be extremely low with suitable and correct application. Institutions and well-known semiconductor manufacturers confirm this.
- In contrast to thermal compounds, ICT phase change materials can be pre-assembled on contact surfaces of component and heat sink. Even before the first heating process, an optimal contact is created. The use of these substrate carrier-coated phase change materials and pure phase change materials in the form of a foil guarantees a high reproducibility
- All phase change material types can be perfect by means of CNC cutting and punching systems in almost all form formats according to customer specifications; also in roll form and on slide carrier (drop & place) and in high quantities
- Costs can be saved by the selective placement of the phase change materials by means of metallic substrate carrier or with a pure phase change compound using foil form in the assembly process
- In case of maintenance/repair, the phase change materials can be easily removed. The contact surfaces of the component and the heat sink can be easily cleaned by means of mineral spirits, solvents or isopropyl alcohol and a soft cloth (microfiber cloth).
- High thermal conductivity > 3.5 to > 220 W/mK(ASTM D 5470) with aluminium substrate carrier
- Minimisation of thermal contact resistance by volumetric expansion by approx. 15-20% and active wetting of the contact surfaces.
- Very low heat transfer resistance 0, 03c °/W
- Silicone-containing but also as silicone-free solid thermal conductive substance – dry on contact
- No curing and bleeding
- No becoming, migration, leakage or pumping in the operating temperature range
- Simple pre-assembling
- Process-sure uniform thickness
- Fast and practical application through block-like fill-up stick and dispenser-like pen
- Very productive (fill-up stick)
- Interchangeability of the material without surface treatment
- Cleaning by Isopropyl alcohol
- Ideal substitute for thermal compound
- As sheet/mat, in roll form or as a compound in cartridges, fill-up stick (container)
- Standard sheet Sizes-sheets | Standard DIN A4/300 mm x 500 mm or 400 mm x 1000 mm
- In blanks and shapes according to customer specification
- Kiss cut parts also on roll
- Loose form stamped parts (delivery also possible on reel)
- Other coating thicknesses can also be requested
- Roll lengths and widths available according to customer requirements (from 15 mm width)
- In roll form, dimensions according to customer specification
- Fast, clean and process-safe pre-assembly by partial adhesive strips on the outside areas of Tim's, (Drop & place) with or without partial stickliner both variants on reel available, also continuously unilaterally available
- In blanks and shapes according to customer specification roll/loose or on carrier (Kisscut)
- IGBT, CPU, high power LED/COB, discrete semiconductor at heat sink/cooling plates/heatsink
- Diodes and rectifiers on heat sinks
- Electronic modules to heat sinks
- Peltier elements
- More
- Laptops (Heatpipe applications)
- Motor Controls for Automotive
- Auxiliary Units Air Conditioning technology and Belüftungssyteme (automotive)
- Automotive Power Supplies
- Railway Technology (Converter)
- High power LED lighting applications stadiums/street lighting (light bulbs)
- White goods (control elements e.g. for induction plates)
- Industrial computers
- UPS Equipment