Stafford, Texas

CEM Evaporator Series, Controlled Evaporator Mixer

CEM Evaporator Series, Controlled Evaporator Mixer

A complete CEM system incorporates a carrier gas flow controller, a liquid flow meter, a 3-way mixing valve (in which the liquid is injected into the carrier gas stream), a heat exchanger (in which total evaporation is achieved), and a readout/control unit including power supply. This system will be sufficient for operation of the gas flow, liquid flow, and temperature required.

Superior Vapor Flow Control
Our unique and patented CEM technology, which stands for Controlled Evaporation Mixing, is developed for accurate vapor flow control. Traditional bubbler systems are often not capable of handling sufficient quantities of liquid with a low vapor pressure, or perform in an imperfect way. Moreover, they cannot instantaneously provide vapor of a mixture of liquids with different vapor pressures. Our evaporation technology is fast, accurate, highly repeatable, and efficient.


  • accurately controlled gas / liquid mixture fast response
  • high reproduceability
  • very stable vapor flow
  • flexible selection of gas / liquid ratio
  • handles water, solvents and mixtures
  • lower working temperature than conventional systems
  • optional control by PC / PLC (RS232 / Fieldbus)


Our CEM systems have successfully been applied in a large number of different applications in wide variety of markets. For example, tools (drills, screwdrivers, saw blades, etc.) and machine parts can be coated to improve their wear resistance using CEM technology. CEMs can also be used for when electric and dielectric (insulating) layers are deposited in semiconductor and solar cell manufacturing processes where the heat insulation of glazing is improved by a coating applied (by CEM) to its surface and the humidity in reactor/process chambers is controlled to ensure optimum performance.

CEM Technology: Controlled Evaporation and Mixing

The CEM-System is an innovative Liquid Delivery System (LDS) that can be applied for atmospheric or vacuum processes. The vapor generation system consists of a (thermal or Coriolis) liquid flow controller, a gas mass flow controller (MFC) for carrier gas and a temperature controlled mixing and evaporation device. The system is suitable for mixing liquid flows of 1-1200 g/h resulting in saturated vapour flows of 50 mln/min up to 100 ln/min. This vaporizer system can replace bubblers. New opportunities created with the CEM-system: mixtures can be evaporated and even solids, dissolved in solvents can be vaporized successfully.

Chemical Vapor Deposition

Chemical Vapor Deposition (CVD) is a chemical process used to produce high-purity, high-performance solid materials. The process is not only used in the semiconductor industry to produce thin films for LEDs, transistors and DRAMs, but also in surface treatment, hardening processes and manufacturing of high temperature superconductors. In a typical CVD process, the surface (wafer or substrate) is exposed to one or more volatile precursors, which react and/or decompose on the substrate surface to produce the desired deposit.

  • ALD (Atomic Layer Deposition) or ALCVD (Atomic Layer CVD): deposits successive layers of different substances to produce layered, crystalline films
  • APCVD (Atmospheric pressure CVD): CVD processes at atmospheric pressure
  • MOCVD (Metal Organic CVD): CVD processes based on metalorganic precursors
  • PECVD (Plasma-Enhanced CVD): CVD processes that utilize a plasma to enhance chemical reaction rates of the precursors
Defined Humidification of Gases

CEM systems are ideally suited for the accurate adjustment of dew or moisture. The intrinsic characteristics of large dynamic range and high accuracy ensure that the moisture level can be controlled with great flexibility from only a few ppm up to virtually 100%, while maintaining a very high stability in dew point. Full functionality is retained with operating pressures as high as 100 bar.

Calibration of Gas Chromatographs, Mass Spectrometers and Gas Sensors

Through the combination of Mass Flow Controllers for liquids and the CEM system, gas phase concentrations can be produced as desired. Thus Mass Spectrometers or Gas Chromatographs can be calibrated as the reference stream from the CEM is both highly reproducible and highly accurate due to the direct action of the Mass Flow Controllers.

Controlled Evaporative Mixer (CEM) Vapor Flow Model Line-Up

Model Description Max. capacity (based on water) Max. capacity Max. temp.
W-101A 10 W, for µ-FLOW 2 g/h Liquid 4 ln/min Gas 392˚F
W-102A 10 W, for LIQUI-FLOW / mini CORI-FLOW 30 g/h Liquid 4 ln/min Gas 392˚F
W-202A 100 W, for LIQUI-FLOW / mini CORI-FLOW 120 g/h Liquid 10 ln/min Gas 392˚F
W-303B 1000 W, for LIQUI-FLOW / mini CORI-FLOW 1200 g/h Liquid 100 ln/min Gas 392˚F