摘要 |
A photoconductive switch comprises a first layer (1) of a first material sandwiches between two contact layers (2,3). The first layer is adapted to be conducting upon applying a voltage across said contact layers when irradiated by light (5) of an energy high enough for lifting charger carriers from the valence band to the conduction band of the first material. A first (2) of the contact layers is provided with apertures (4) for allowing light applied on the switch to reach said first layer there for making the switch conducting upon applying a voltage across the two contact layers. A thin second layer (7) is arranged on the side of the first contact layers, at least covering the surfaces of the first layer exposed through said apertures and forming an interface to said first layer in said apertures. The second layer is made of a material being able to form a well ordered interface to said first material and having the same or a larger band gap than the latter. |