Epitaxy, often called Epi, is the process of depositing highly controlled silicon-based crystalline films, a critical process technology for creating advanced transistors and memories, and for wafer manufacturing.

About epitaxy

Precise temperature control 

Epitaxy is a high-temperature process, and precise temperature control is extremely important in Epi reactors. ASM has developed new methods of temperature control in our epitaxy tools that enable improved film performance and repeatability in volume production.  

Applications for advanced transistors 

Epitaxy processes include silicon-based compounds, such as silicon (Si), silicon-germanium (SiGe) and silicon phosphorus (SiP), used for transistor strain and channel layers. Strained silicon is a silicon layer in which the atoms are stretched beyond their normal interatomic distance, allowing higher electron mobility. This results in faster transistor switching at lower power.  

Selective for precision 

Selective epitaxy is a process that only deposits silicon or a silicon compound on certain predetermined areas of the wafer. Epitaxial layers are deposited selectively to form the transistor channel region, as well as the source and drain. 

The source is the point where charge carriers like electrons enter the channel, and the drain is where they leave. Between them is the gate that controls the conductivity of the channel. It can be switched to allow electrons to flow or to prevent them from flowing. By combining additional elements in the processing source gases, manufacturers can customize Epi films to very precise concentrations of the dopant elements. 

Our epitaxy soloutions

Epitaxy involves the deposition of silicon or silicon compounds to form layers that help to continue and perfect the crystal structure of the bare silicon wafer below. It improves the electrical characteristics of the wafer surface, making it suitable for highly complex microprocessors and memory devices. 

Epsilon® 2000 Epitaxy

Our Epsilon 2000 single-wafer epitaxy tool offers a wide variety of epitaxy applications for 150mm and 200mm wafers. They range from high-temperature silicon for wafer preparation to low-temperature selective or non-selective silicon germanium (SiGe) for forming transistor strain layers.

Epsilon® 2000 Epitaxy

Intrepid® ES™ & Intrepid® ESA™ Epitaxy

The Intrepid® ES™ is our most advanced epitaxy deposition tool. It is designed for the most critical 300mm applications for advanced transistors and memories.

Intrepid​​​® ES™ & Intreprid® ESA™ Epitaxy

Technology and products

We have a proven track record of innovation, spanning a wide range of equipment and process technologies now used by the world’s leading semiconductor manufacturers.

  • Atomic Layer Deposition

    Atomic Layer Deposition, or ALD, is one of our technological solutions that works at a tiny level to make a huge difference.

  • Silicon carbide

    Process equipment for epitaxial deposition of silicon carbide (SiC) is a fast-growing market, mostly due to the material’s benefits for electric vehicles. With our history in epitaxy equipment, this is a natural fit for our line-up.


    PECVD is another process solution we offer to deposit dielectric thin films at relatively low temperatures.

  • Vertical furnaces

    Vertical furnaces offer very high productivity solutions for a wide range of thermal processes including low pressure chemical vapor deposition (LPCVD), diffusion and oxidation.