EpiTwin TT is the twin brother of LayTec’s EpiTT sensor and has two optical heads for measurements at two independent positions. This sensor system is especially designed for application in Close-Coupled Showerhead® (CCS) MOCVD reactors in GaN LED production.

EpiTriple TT respectively offers three optical heads for even larger reactors. On request, we offer metrology systems with 4 (EpiTT Quatro) or more optical heads for complete control.

The combination with the curvature head EpiCurve^® is highly recommended (EpiCurveTwin TT and EpiCurveTriple TT).

Like EpiTT, the multiple head systems combine reflectance and emissivity-corrected pyrometry allowing an accurate online surface temperature measurement better than ±1 K and online growth-rate analysis with an accuracy of up to ±0.001nm/s.

For further details see:

• EpiTwinTT datasheet
• EpiCurveTwin TT datasheet
• related application notes

Control and analysis software: EpiNet 1.10

• best performance and reliability for production environments
• convenient display showing temperature, growth rate, refractive index and absorption coefficient
• two user levels for configuration and calibration (operator and advanced)
• integration into epitaxy control software (e.g. AIXact)
• convenient remote control features from the growth recipe
• linescans across each wafer and the whole susceptor
• in multi-wafer systems: measurement at different positions on the wafer providing reflectance and temperature gradients across each wafer
• automated growth rate fits after the run