Growth monitoring in real time
From interference-caused fluctuations in wafer reflectivity during film growth, films thicker than 40 nm can be precisely determined to 1 nm. With its two reflectivity measuring angles with measuring wave lengths of 450 nm and 950 nm, Pyritte is suitable for thin and thick films.
Together with the controller of the system Pyritte monitors the growth of the individual films and permits real-time diagnosis of the cutting process. The patented principle of reflection-supported pyrometry used for temperature measurement offers much greater accuracy than conventional pyrometers. Interference-caused reflectivity variations of the wafer during the coating is also measured and included in temperature calculations.
Scope of delivery
- Basic unit with remote optics
- Distance between optic head and basic unit: 1.8 meter
- Distance between basic unit and PC: up to 100 m
- PC with interface for communication with the system controller
- Standard mounting: Viewport adapter for 1.33" flange
Conditions for use
- Substrate material: GaAs, SiGe, InP and other opaque materials in the working temperature range for the measuring wavelengths
- System types: MBE or MOVPE
- Viewport with at least 13 mm of free cross section vertical to sample
- Distance of Viewport to wafer: < 500 mm
- Angular encoder signals for multi-wafer systems
- Digital control signals for start and stop of layer |