Micro heat exchangers are used in process technologies to precisely adjust the temperature of fluids. In their most simple form, they consist of square foils provided with microchannels, which are stacked on top of each other at an angle of 90 degrees and connected by e.g. diffusion welding. The microchannels of one foil, also called passage, are arranged parallel to each other in straight lines on a plane. In flow direction, they have constant cross sections. Standard heat transfer, however, is characterized by a highly distorted temperature profile of the fluids leaving the microchannels when the flow rates are small. Due to the cross-flow design, the fluid in the individual microchannels is heated or cooled to variable degrees. As a result, the viscosity of the media flowing in the channels varies strongly, which leads to variable mass flows. This adversely affects the residence time behavior of the heat exchanger. A novel cross-flow micro heat exchanger made by KIT solves this problem. The passage for temperature adjustment is modified geometrically. The heat exchanger developed by scientists of the Institute for Micro Process Engineering (IMVT) is provided with funnel-shaped microchannels. The channel widths of the first passage increase in flow direction. The channels of the second passage have a constant flow cross section. The combination of both variably structured metal foils ensures homogeneous temperature and residence time distribution in the channels of the second passage. KIT searches for industry partners using this new micro heat exchanger.