To overcome the challenges that occur with larger wafers (4", 6" or 8"), you need the advanced EpiCurve® TT system. It combines wafer curvature measurements with all the features of the EpiTT: emissivity-corrected pyrometry and growth rate/thickness measurements by three-wavelength reflectance. This tool will help you avoid cracks, achieve flat wafers and control temperature homogeneity. Every curvature tool can be equipped with Advanced Resolution (AR) curvature measurements for wafer bow asphericity control (EpiCurve®TT AR).

LayTec has customized and expanded EpiCurve®TT's performance for VCSEL epitaxy: an additional measurement head for spectral reflectance sensing can be mounted on a conventional EpiCurve®TT system. This allows integrating the full EpiCurve®TT performance with the spectral monitoring of DBR stop-bands and cavity dip position. ...more


LayTec offers combinations of EpiCurve® TT with the products of the EpiTT family: EpiCurve®Twin TT has a total of two EpiTT heads and EpiCurve®Triple TT has three EpiTT optical heads to measure temperature and reflectance at independent positions.


When it comes to bowed IR transparent substrates like sapphire or SiC, a conventional infrared (IR) pyrometer can measure only the pocket temperature. LayTec's Pyro 400 directly measures surface temperature of GaN on sapphire and of SiC and enables direct temperature control of InGaN MQW layers.###HIDE### The combination of Pyro 400 and EpiCurve® TT will provide you with all real-time growth parameters and the best monitoring of quantum well growth in blue and green LEDs and laser diodes.   ... more


For precise temperature measurements throughout the whole fab, we offer the unique temperature calibration tool AbsoluT. It will help you set up exactly the same absolute temperature reference point for pyrometry measurements on different rings and in different reactors and runs.   ...more


All LayTec in-situ systems are equipped with LayTec software specially developed for process optimization, analysis and control. Our software solutions can be integrated into the whole fab to monitor all runs simultaneously and support operators making “stop or go” decisions. ... more


Each product in the  EpiCurve® TT family is available for all MOCVD growth systems, such as- systems with satellite rotation, showerhead-like systems, R&D type and customized MOCVD growth systems and others. For details please download the EpiCurve® TT datasheet


Detecting thin-film strain in-situ during epi growth through the tiny openings of the showerhead view-ports is a challenge. However, with our advanced software algorithms, in-situ strain balancing or AlGaN lattice constant tuning is now possible with accuracy levels formerly known only for ex-situ XRD methods. ...more


LayTec’s sensors are adaptable to many MBE systems by Riber, Veeco, DCA and VG. Adaptation to other manufacturers’ products and custom-built systems is available on request. To learn more please download our Application Note: EpiCurve® TT for MBE


To see LayTec in-situ metrology live, you can watch a video that we have taken at a customer site. In a short lab tour at FBH Berlin in Germany you will see how EpiCurve® TT and EpiRAS TT monitor LED and laser growth and help optimize the processes. ... more


Product information

Fields of application

  • GaN LED and laser diode production
  • III-Nitride growth on silicon
  • GaAs/AlGaInP/InP laser diode production
  • Triple-junction solar cell production on GaAs, Ge, Si
  • SiC for power electronics
  • R&D for new materials and devices

Product Features


  • Wafer-selective curvature measurements in the curvature range from -7000 km-1 (convex) to +800 km-1 (concave)
  • Versions with a blue laser provide measurements on double-sided polished and patterned substrates
  • Aspherical bowing curvature measurements with an Advanced Resolution (AR) option

Emissivity Corrected Pyrometry:

  • Temperature range: T = 450°C to 1300°C for large viewport systems / T = 500°C to 1400°C  for narrow viewport systems / other temperature ranges on request, e.g. 1500°C for UV LED applications, 1700°C for SiC
  • Accuracy better than 1 K
  • Wafer and area selective measurements
  • True wafer temperature for opaque semiconductors such as InP, Graphite (SbS)
  • Pocket temperature for GaN, Sapphire and SiC

Reflectance at three wavelengths:

  • 950 nm, 633 nm and 405 nm
  • growth rate, layer thickness, roughness and other layer qualities