720 results about "Valence band" patented technology

A thin film transistor, which is capable of improving carrier mobility, and a display device and an electronic device, each of which uses the thin film transistor, are provided. The thin film transistor includes: a gate electrode; an oxide semiconductor layer including a multilayer film including a carrier travel layer configuring a channel and a carrier supply layer for supplying carriers to the carrier travel layer; a gate insulating film provided between the gate electrode and the oxide semiconductor layer; and a pair of electrodes as a source and a drain. A conduction band minimum level or a valence band maximum level corresponding to a carrier supply source of the carrier supply layer is higher in energy than a conduction band minimum level or a valence band maximum level corresponding to a carrier supply destination of the carrier travel layer.

A photo-detector comprising: a photo absorbing layer comprising an n-doped semiconductor exhibiting a valence band energy level; a barrier layer, a first side of the barrier layer adjacent a first side of the photo absorbing layer, the barrier layer exhibiting a valence band energy level substantially equal to the valence band energy level of the doped semiconductor of the photo absorbing layer; and a contact area comprising a doped semiconductor, the contact area being adjacent a second side of the barrier layer opposing the first side, the barrier layer exhibiting a thickness and a conductance band gap sufficient to prevent tunneling of majority carriers from the photo absorbing layer to the contact area and block the flow of thermalized majority carriers from the photo absorbing layer to the contact area. Alternatively, a p-doped semiconductor is utilized, and conductance band energy levels of the barrier and photo absorbing layers are equalized.

The present invention is generally directed to nanocomposite thermoelectric materials that exhibit enhanced thermoelectric properties. The nanocomposite materials include two or more components, with at least one of the components forming nano-sized structures within the composite material. The components are chosen such that thermal conductivity of the composite is decreased without substantially diminishing the composite's electrical conductivity. Suitable component materials exhibit similar electronic band structures. For example, a band-edge gap between at least one of a conduction band or a valence band of one component material and a corresponding band of the other component material at interfaces between the components can be less than about 5kBT, wherein kB is the Boltzman constant and T is an average temperature of said nanocomposite composition.

The invention discloses a semiconductor device, which comprises a substrate, a plurality of gate stacking structures on the substrate, a plurality of gate side wall structures on the two sides of each gate stacking structure, and a plurality of source-drain regions in the substrate on the two sides of each gate side wall structure. The gate stacking structures comprise a plurality of first gate stacking structures and a plurality of second gate stacking structures, wherein each first gate stacking structure comprises a first gate insulating layer, a first work function metal layer, a second work function metal diffusion barrier layer and a gate filling layer, and the work function is close to a valance band (conduction band) side. Each second gate stacking structure comprises a second gate insulating layer, a modified first work function metal layer, a second work function metal layer and a gate filling layer. The semiconductor device is characterized in that the second work function metal layer comprises injected doping ions for adjusting the work function, and part of the first work function layer which is diffused below the second work function mental layer is used for adjusting a threshold to enable the work function of a gate to be close to the conduction band (valence band) side and to correspond to a first work function, so that the work function of the gate is accurately adjusted.

A tunnel junction structure comprises an n-type tunnel junction layer of a first semiconductor material, a p-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. The first semiconductor material includes gallium (Ga), nitrogen (N), arsenic (As) and is doped with a Group VI dopant. The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer. Doping the first semiconductor material n-type with a Group VI dopant maximizes the doping concentration in the first semiconductor material, thus further improving the probability of tunneling.

In one embodiment, a first transistor is comprised of a first p+ source region doped in an n-well in the substrate and a first n+ drain region doped on one side at the top of the pillar. A second transistor is comprised of a second p+ source region doped into the second side of the top of the pillar and serially coupled to the top drain region for the first transistor. A second n+ drain region is doped into the substrate adjacent the pillar. Ultra-thin body layer run along each pillar sidewall between their respective active regions. A gate structure is formed along the pillar sidewalls and over the body layers. The transistors operate by electron tunneling from the source valence band to the gate bias-induced n-type channels, along the ultra-thin silicon bodies, thus resulting in a drain current.