Fraunhofer-gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Mergeoptics Gmbh

Axel Hülsmann

Karl-Friedrich Becker

Harald Von Rosenberg

A millimeter-wave radar device including at least one millimeter-wave circuit and at least one antenna, wherein the millimeter-wave radar device is designed as a module having a multilayered multipolymer circuit board having at least a first layer composed of a polymer material having low dispersion of the dielectric constant, a second layer composed of a high-strength polymer material, which stabilizes the multipolymer circuit board, and a metallization layer, which is arranged between the first layer and the second layer and serves for shielding and for signal carrying, and the multipolymer circuit board carries the at least one millimeter-wave circuit and the at least one antenna.

Millimeter-wave radar

The invention relates to a heterobipolar transistor, comprising an emitter which includes a first semiconductor layer () made of a first semiconductor material and a second semiconductor layer () made of a second semiconductor material, a band gap value of the first semiconductor material being smaller than a band gap value of the second semiconductor material. A semiconductor intermediate layer () made of an intermediate layer semiconductor material is disposed between the first semiconductor layer () and the second semiconductor layer () and a band gap value of the intermediate layer semiconductor material is greater than the band gap value of the first semiconductor material and smaller than the band gap value or the second semiconductor material. A potential barrier forms at the interface between two semiconductor materials having different band gap values and a stream of electrons must tunnel through it. It is easier for electrons jointly to tunnel through the energy barriers occurring at the interfaces of the semiconductor intermediate layer () than to tunnel through one energy barrier forming at an interface between the first semiconductor layer () and the second semiconductor layer () without an energy barrier generating semiconductor intermediate layer positioned between them. The resistance of the heterobipolar transistor emitter arrangement thus in lowered by the invention.

Growing community of inventors

Freiburg, Germany

Axel Hülsmann