DEVICE AND METHOD FOR EVAPORATING AN ORGANIC POWDER

In a method for evaporating a non-gaseous starting material, the starting material is introduced into an evaporation chamber; an evaporation element heats the starting material to create a vapor; a conveying gas flow transports the vapor through a conveying channel and past a sensor, which measures the concentration or partial pressure of the vapor in the gas flow flowing through the conveying channel; and the mass flow of the vapor through the conveying channel is controlled by varying the conveying gas flow with respect to a setpoint value. To keep the vapor flow largely constant over time, a compensating gas flow is fed into the conveying channel at a mixing point disposed between the evaporator and the sensor. A second mass flow controller controls the mass flow of the compensating gas flow such that, when the conveying gas flow varies, the gas flow flowing past the sensor remains constant.