Semiconductor memory devices

A semiconductor memory device, comprising:

• semiconductor layers of opposite conductivity type defining a p-n junction,
• a plurality of layers of semiconductor materials located in the space charge region of said p-n junction, said semiconductor layers having an energy band diagram which is a sequence of conduction band edge discontinuities and valence band edge discontinuities which are in the same direction in said energy diagram, said discontinuities forming potential wells for confinement of electrons and holes,
• means for producing electrons and holes for confinement in said potential wells in said semiconductor layers,
• means for detecting the presence of electrons and holes in said potential wells.

A semiconductor storage device, comprising:

• a heterostructure comprising alternating layers of different semiconductor materials, said heterostructure having an energy band diagram exhibiting conduction band edge discontinuities and valence band edge discontinuities which are in the same direction in said energy diagram, said alternating layers providing spatially displaced electron wells and hole wells,
• means for producing electrons and holes said electron and hole wells.
• means for detecting the presence and absence of electrons and holes in said wells,
• means for removing electrons and holes confined in said wells.

A semiconductor storage device, comprising:

• a periodic semiconductor structure comprising alternating layers of different semiconductor materials having substantially the same thickness, said periodic structure having an energy band diagram which is a periodic series of conduction band edge and valence band edge discontinuities which are in the same direction in said energy diagram,
• means for producing electrons and holes which are confined by said discontinuities,
• means for detecting the presence of said confined electrons and holes, and
• means for removing electrons and holes from confinement by said discontinuities.

A semiconductor storage device, comprising:

• a periodic structure comprised of a series of p-n junctions, the energy diagram of such structure being a series of potential wells for electrons and holes, said wells for electrons being spatially separated from said wells for holes,
• means for producing electrons and holes in said separated wells,
• means for detecting the presence or absence of electrons and holes in said wells, and
• means for removing electrons and holes from said wells.