An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device, and manufacturing method thereof

Various structures and methods for improving the performance of trench-shielded power semiconductor devices and the like are described.

Structures and methods for improving trench-shielded semiconductor devices and schottky barrier rectifier devices

Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.

Trench-based power semiconductor devices with increased breakdown voltage characteristics

The semiconductor component, such as a Schottky diode with a low leakage current, has a metal-semiconductor junction between a first metal electrode and the semiconductor. The semiconductor, which is of a first conductivity type, has a defined drift path and a plurality of supplementary zones of a second conductivity type extending from the semiconductor surface into the drift path. A number of foreign atoms in the supplementary zones is substantially equal to a number of foreign atoms in intermediate zones surrounding the supplementary zones and the number of foreign atoms does not exceed a number corresponding to a breakdown charge of the semiconductor.

Semiconductor component with metal-semiconductor junction with low reverse current

A high withstand voltage semiconductor device does not show any significant fall of its withstand voltage if the impurity concentration of the RESURF layer of a low impurity concentration semiconductor region thereof varies from the optimal level and/or influenced by the fixed electric charge. The device is produced by forming a ring-shaped high impurity concentration edge termination layer of a second conductivity type and a ring-shaped low impurity concentration RESURF layer of the second conductivity type on the front surface of a semiconductor layer of a first conductivity type carrying electrodes respectively on the opposite surfaces thereof along the outer edge of one of the electrodes, then forming an outer ring layer with an impurity concentration substantially as low as the RESURF layer concentrically outside the RESURF layer with a gap separating therebetween and subsequently forming an inner ring layer with an impurity concentration substantially as high as the edge termination layer concentrically inside the RESURF layer.

High withstand voltage semiconductor device

A semiconductor device has a first diode having a pn junction and a second diode having a combination of a Schottky barrier and a pn junction in a current-passing direction provided side by side in a direction perpendicular to the current-passing direction. When a forward current with a current density JF is passed into the second diodes, the relation ##EQU1## is established in a forward voltage VF range of 0.1 (V) to 0.3 (V), where k represents the Boltzmann constant, T represents the absolute temperature, and q represents the quantity of electron charges. The first diode is constituted by a first semiconductor region of one conductive type and a second semiconductor region of the other conductive type provided so as to be adjacent to the first semiconductor region to form a pn junction, so as to be in ohmic contact with one main electrode, and so as to have an impurity concentration higher than that of the first semiconductor region, and the second diode is constituted by the first semiconductor region of the one conductive type and a third semiconductor region of the other conductive type provided so as to be adjacent to the first semiconductor region to form a pn junction, so as to be in contact through a Schottky barrier with the one main electrode, and so as to have an impurity concentration higher than the first semiconductor region.

Semiconductor schottky device with pn regions

In a semiconductor device a first diode having a pn junction and a second diode having a combination of a Schottky barrier and a pn junction in a current-passing direction are provided side by side in a direction perpendicular to the current-passing direction. When a forward current with a current density J F is passed into the second diodes, the relation is established in a forward voltage V F range of 0.1 (V) to 0.3 (V). The first diode is constituted by first and second semiconductor regions (13, 15) forming a pn junction therebetween, the second being in ohmic contact with one main electrode (3), and having an impurity concentration higher than that of the first semiconductor region (13). The second diode is constituted by first and third semiconductor regions (13, 16) forming a pn junction therebetween, the third being in contact through a Schottky barrier with the one main electrode (3) and having an impurity concentration higher than the first semiconductor region (13).

Yasumiti Yasuda

Papers

Semiconductor schottky device with pn regions

High-speed diode and method for producing the same