Unitemp (Germany) RSO series vacuum reflow ovens with bottom infrared lamp heating: up to 650°C, ramp-up up to 10 K/s and temperature uniformity within 1% of set point. RSO-210 takes 210 × 210 mm substrates or 8" wafers, RSO-300 takes 300 × 300 × 40 mm parts; vacuum 1×10⁻³ hPa (10⁻⁶ hPa range on HV versions), up to 4 MFC gas lines and formic acid flux-free soldering.
Infrared Vacuum Reflow Ovens up to 650°C
The Unitemp (Germany) RSO series are vacuum reflow ovens heated by infrared lamps, reaching up to 650°C. They handle leaded and lead-free solder pastes as well as high-temperature reflow of ceramic/alumina hybrid assemblies. The compact units fit on a lab bench for process development and are also suited to small-batch and series production.
RSO-210 takes substrates up to 210 × 210 mm or 8″ wafers; RSO-300 takes parts up to 300 × 300 mm and 40 mm high. Bottom infrared lamps heat the chamber, a quartz holder with graphite susceptor is included, ramp-up reaches 10 K/s and temperature uniformity is within 1% of set point. Parts are cooled with nitrogen — about 200 K/min from 650°C to 400°C.
One nitrogen MFC (5 nlm) is standard, expandable to 4 gas lines, for oxygen, hydrogen, forming gas and formic acid. Vacuum is 1×10⁻³ hPa, with high-vacuum (-HV) versions in the 10⁻⁶ hPa range. Interlock and an emergency-off button are standard.
The SIMATIC® controller with a swivel 7″ touch panel stores 50 programs of 50 steps and continuously logs temperature, gas flow, cooling water and pressure. A second process chamber can be added on the same controller, so different processes do not require cleaning the chamber in between.
Models and Specifications
| Item | RSO-210 | RSO-300 / RSO-300-HV |
|---|---|---|
| Max. part size | 210 × 210 mm or 8" wafer | 300 × 300 × 40 mm |
| Process chamber (W × D × H) (mm) | 230 × 400 × 40 | 309 × 319 × 40 |
| Chamber material | Aluminum (quartz chamber optional) | |
| Part holder | Quartz holder with graphite susceptor (standard) | Quartz holder with graphite susceptor (standard); 3-arm / 4-arm quartz holders optional |
| Max. temperature | 650°C (1000°C optional) | 650°C (higher on request) |
| Temperature uniformity | ≤ 1% of set temperature | |
| Heating | Bottom infrared lamps | |
| Max. ramp-up rate | 10 K/s | |
| Ramp-down rate | 650→400°C: 200 K/min; 400→100°C: 30 K/min | |
| Vacuum | 1×10⁻³ hPa; 10⁻⁶ hPa range on HV version | 1×10⁻³ hPa; 10⁻⁶ hPa range on RSO-300-HV |
| Process gas lines | Nitrogen MFC 5 nlm × 1, up to 4 lines | |
| Process gases | Inert gas, oxygen, hydrogen, forming gas, formic acid | |
| Controller | SIMATIC® 7" swivel touch panel; 50 programs × 50 steps | |
| Cooling | Water-cooled chamber; parts cooled by nitrogen | |
| Safety | Interlock and emergency-off button (standard) | |
| Dimensions (W × D × H) (mm) | 505 × 525 × 570 | 578 × 496 × 570 |
| Weight (kg) | 60 | 70 |
| Power supply | 3 × 400 V 3-phase, 11 kW; or 3 × 208 V, 10 kW | |
Highlighted rows differ between models; values shared by all models are merged into one cell.
For formic acid modules (FA I–FA IV), formic acid and flux traps, oxygen and moisture analyzers, a second process chamber, floor cabinets and other options, please contact Utrun-Tech.
For full specifications and dimensional drawings, see the Unitemp RSO series page and datasheets.
Typical Applications
Flux-free vacuum reflow
Vacuum reflow in nitrogen or formic acid without flux or cleaning, for leaded and lead-free SMT reflow, pin-in-paste reflow and LED attach.
High-temperature ceramic hybrid soldering
Up to 650°C (1000°C optional on RSO-210) for ceramic/alumina hybrid assemblies and other high-temperature solders.
Semiconductor and wafer process development
Takes 8" wafers or 300 × 300 mm substrates; fast, uniform infrared heating for R&D and small series, as well as production.
Frequently Asked Questions
How does the RSO series differ from the RSS series?
RSS is a benchtop unit with a heated plate, up to 400°C. RSO uses bottom infrared lamps, reaches 650°C (1000°C optional on RSO-210), ramps up at up to 10 K/s and cools parts directly with nitrogen. Choose RSO for high-temperature solders, ceramic hybrids or faster ramp-up; RSS is usually enough for flux-free soldering of standard pastes and lab prototyping.
RSO-210 or RSO-300?
By part size: RSO-210 takes 210 × 210 mm substrates or 8" wafers, RSO-300 takes parts up to 300 × 300 mm and 40 mm high. Maximum temperature, ramp rate, gas lines and controller are the same. For high vacuum in the 10⁻⁶ hPa range, choose the HV version.
Can one oven run two different processes?
Yes — a second process chamber (RSO-PC-210 / RSO-PC-300) can be added, sharing one controller. If two processes would contaminate each other (for example one with flux and one flux-free), you avoid cleaning the chamber at every changeover, at lower cost than a second oven.