Metal-semiconductor-metal photodetector
AssigneeHitachi, Ltd.
InventorJeremy Allam
Life of this patent
Estimating the term…
Abstract
A metal-semiconductor-metal (MSM) device comprises interdigitated metal electrodes (2, 3) on a semiconductor substrate (1). When embodied as a photoconductor, a photoconductive region (4) is bounded by layers (5, 6) which form a resonant cavity for incoming radiation to improve the response. In another embodiment, which can be either a photodiode or photoconductor, the electrodes are arranged to extend into the thickness of the photoresponsive layer (4). To reduce sensitivity to polarization,the electrodes may be arranged in sets extending in mutually transverse directions. Groups of the electrodes may be connected so as to be sensitive to polarization but substantially insensitive to the amplitude of incoming radiation.
Claims20
A metal-semiconductor-metal MSM photoconductor device comprising:
- a photoconductive region for generating charge carriers in response to incoming optical radiation,
- an array of electrodes for applying an electric field to the photoconductive region so as to collect charge carriers produced in response to the incoming radiation, and
- means defining an optical resonant cavity containing the photoconductive region, whereby incoming optical radiation resonates in the cavity to generate said carriers.
A metal-semiconductor-metal (MSM) detector comprising:
- a substrate,
- a photoconductive layer overlying substrate for generating charge carriers in response to incoming radiation, and
- electrode means to receive carriers from the photoconductive layer produced by the incoming radiation, said electrode means comprising electrically conductive regions extending into the thickness of the photoconductive layer for establishing an electric field through the layer between the conductive regions.
A metal-semiconductor-metal (MSM) detector device comprising:
- a photoresponsive region for generating charge carriers in response to incoming optical radiation, and
- electrode means to receive carriers from the photoresponsive region produced by the incoming radiation, said electrode means comprising first and second interdigitated sets of electrodes, the electrodes of at least one of sets including portions which extend in mutually transverse directions whereby to desensitize the response of the device to the polarization of the incoming radiation.
A metal-semiconductor-metal (MSM) detector device comprising:
- a photosensitive region for generating charge carriers in respect to incoming radiation, and
- electrode means to receive carriers from the photoresponsive region produced by the incoming radiation, said electrode means comprising a plurality of sets of interdigitated electrodes interconnected to provide an output which is sensitive to the polarization of incoming radiation but substantially insensitive to the intensity thereof at least over a given intensity range.
Dependencies are inferred from the claim text.