Neocera radiative substrate heaters provide a maximum substrate temperature of 850°C. The heaters are UHV compatible and also Oxygen compatible up to a maximum of 1 atmosphere of Oxygen. The radiative heating element is a resistive coil with a maximum working temperature of 1050˚C, facilitating a maximum substrate temperature of 850˚C. The primary heating of the substrates is through radiation from the heating coil. K-type thermocouple laser-welded to the heating coil provides input to the PID temperature controller. The actual substrate temperature is measured by a calibrated external pyrometer. The radiative heaters are available in various substrate sizes (2-inch, 4-inch, 6-inch and 8-inch), 2-inch being the most common. When smaller substrate sizes are used, various types of substrate carriers/inserts can be provided as shown below. The wafer carriers used in radiative heaters are load-lock compatible.