 The kSA BandiT is a non-contact, non-invasive, real-time wafer temperature sensor. The system utilizes the temperature-dependent optical absorption edge of semiconductor materials. kSA BandiT provides a viable solution for low–temperature wafer monitoring where pyrometers cannot measure. It is also insensitive to changing view port transmission, stray light sources, and signal contribution from substrate heaters.
Diffusely scattered light from the semiconductor wafer is detected to measure the bandgap absorption edge. From the bandgap absorption edge the temperature is accurately determined. The kSA BandiT can run in two modes: 1) transmission mode, where the substrate heater is used as the light source and a single detector port is required. 2) reflection mode, where a light source is mounted on one port and the detector unit is mounted on a 2nd, non-specular port. The kSA BandiT is available in two models covering the spectral range 380 nm – 1400 nm. Dual spectrometer units are also available for applications requiring the full spectral range. Typical substrate materials include GaAs, Si, SiC, InP, ZnSe, ZnTe, and GaN.
The kSA BandiT temperature sensor can run from a laptop computer using a single USB cable connection. Full software control of the light source, spectrometer, and data I/O facilitates system control. Temperature readings can be mapped to analog output channels, and analog input channels may be used to read external signals such as thermocouples, simultaneously with the kSA BandiT temperature reading. All acquired data may be stored, processed, and exported to common file types.
|
