초록 ▼

A semiconductor device for detecting radiation includes a plurality of quantum well layers, each of which has bound ground and excited states, interleaved with a plurality of superlattice barrier layers, each of which has a miniband of energy states. By selection of the thicknesses and compositions

A semiconductor device for detecting radiation includes a plurality of quantum well layers, each of which has bound ground and excited states, interleaved with a plurality of superlattice barrier layers, each of which has a miniband of energy states. By selection of the thicknesses and compositions of the layers, the excited states of the quantum wells have energies that are approximately equal to energies of states in the minibands. Thus, the excited states and minibands form a band of energy states that is substantially continuous across the pluralities of layers. Carriers are excited from the quantum wells' ground states to the excited states by photon absorption and are swept into and through the minibands by an externally applied electric field. The carriers are collected as photocurrent. The excited states may be selectively positioned in the minibands to tailor the properties of the devices, which can have both n-type and p-type dopants. Devices that respond to more than one wavelength band are also disclosed.

대표청구항 ▼

[ What is claimed is:] [1.] A semiconductor miniband-transport quantum well detector, comprising:a substrate;means, disposed on the substrate, for absorbing incident photons, the absorbing means comprising a multilayer structure including a plurality of quantum well layers, each quantum well layer h

[ What is claimed is:] [1.] A semiconductor miniband-transport quantum well detector, comprising:a substrate;means, disposed on the substrate, for absorbing incident photons, the absorbing means comprising a multilayer structure including a plurality of quantum well layers, each quantum well layer having a bound ground energy state and a bound excited energy state, and a plurality of superlattice barrier layers, each of said superlatice barrier layers having a miniband of energy states in resonance with the excited energy states of its adjacent quantum well layers; andfirst and second contact layers disposed on top and bottom surfaces, respectively, of the multilayer structure;wherein the minibands and excited energy states provide an electrically continuous channel across the layers for carriers excited from the ground energy states to the excited energy states and minibands by absorption of photons when different potentials are applied to the contact layers, and the minibands are at least about fifty meV wide.