Abstract: Provided are a high electron mobility transistor (HEMT) and a method of manufacturing the HEMT. The HEMT includes: a channel layer comprising a first semiconductor material; a channel supply layer comprising a second semiconductor material and generating two-dimensional electron gas (2DEG) in the channel layer; a source electrode and a drain electrode separated from each other in the channel supply layer; at least one depletion forming unit that is formed on the channel supply layer and forms a depletion region in the 2DEG; at least one gate electrode that is formed on the at least one depletion forming unit; at least one bridge that connects the at least one depletion forming unit and the source electrode; and a contact portion that extends from the at least one bridge under the source electrode.

Abstract: A High electron mobility transistor (HEMT) includes a source electrode, a gate electrode, a drain electrode, a channel forming layer in which a two-dimensional electron gas (2DEG) channel is induced, and a channel supplying layer for inducing the 2DEG channel in the channel forming layer. The source electrode and the drain electrode are located on the channel supplying layer. A channel increase layer is between the channel supplying layer and the source and drain electrodes. A thickness of the channel supplying layer is less than about 15 nm.

Abstract: A multi-valued logic device having an improved reliability includes a conversion unit configured to convert a multi level signal into a plurality of partial signals; and a plurality of nonvolatile memory devices configured to individually store the plurality of partial signals, wherein a number of bits of each of the plurality of partial signals individually stored in the plurality of nonvolatile memory devices is less than the number of bits of the multi level signal.

Abstract: According to example embodiments, a higher electron mobility transistor (HEMT) may include a first channel layer, a second channel layer on the first channel layer, a channel supply on the second channel layer, a drain electrode spaced apart from the first channel layer, a source electrode contacting the first channel layer and contacting at least one of the second channel layer and the channel supply layer, and a gate electrode unit between the source electrode and the drain electrode. The gate electrode unit may have a normally-off structure. The first and second channel layer form a PN junction with each other. The drain electrode contacts at least one of the second channel layer and the channel supply layer.

Abstract: According to an example embodiment, a power electronic device includes a first semiconductor layer, a second semiconductor layer on a first surface of the first semiconductor layer, and a source, a drain, and a gate on the second semiconductor layer. The source, drain and gate are separate from one another. The power electronic device further includes a 2-dimensional electron gas (2DEG) region at an interface between the first semiconductor layer and the second semiconductor layer, a first insulating layer on the gate and a second insulating layer adjacent to the first insulating layer. The first insulating layer has a first dielectric constant and the second insulating layer has a second dielectric constant less than the first dielectric constant.

Abstract: According to example embodiments, a method for controlling a gate voltage applied to a gate electrode of a high electron mobility transistor (HEMT) may include measuring a voltage between a drain electrode and a source electrode of the HEMT, and adjusting a level of the gate voltage applied to the gate electrode of the HEMT according to the measured voltage. The level of the gate electrode may be adjusted if the voltage between the drain electrode and the source electrode is different than a set value.

Abstract: According to an example embodiment, a high electron mobility transistor (HEMT) includes a substrate, a buffer layer on the substrate, a channel layer on the buffer layer, and a barrier structure on the channel layer. The buffer layer includes a 2-dimensional electron gas (2DEG). A polarization of the barrier structure varies in a region corresponding to a gate electrode. The HEMT further includes and the gate electrode, a source electrode, and a drain electrode on the barrier structure.

Abstract: A storage node of a magnetic memory device includes: a lower magnetic layer, a tunnel barrier layer formed on the lower magnetic layer, and a free magnetic layer formed on the tunnel barrier. The free magnetic layer has a magnetization direction that is switchable in response to a spin current. The free magnetic layer has a cap structure surrounding at least one material layer on which the free magnetic layer is formed.

Abstract: High electron mobility transistors (HEMTs) and methods of manufacturing the same. A HEMT may include a channel layer and a channel supply layer, and the channel supply layer may be a multilayer structure. The channel supply layer may include an etch stop layer and an upper layer on the etch stop layer. A recess region may be in the upper layer. The recess region may be a region recessed to an interface between the upper layer and the etch stop layer. A gate electrode may be on the recess region.

Abstract: Example embodiments relate to a method of forming a core-shell structure. According to a method, a region in which the core-shell structure will be formed is defined on a substrate, and a core and a shell layer may be sequentially stacked in the defined region. A first shell layer may further be formed between the substrate and the core. When the core and the shell layer are sequentially stacked in the core-shell region, the method may further include forming a groove on the substrate, forming the first shell layer covering surfaces of the groove, forming the core in the groove of which surfaces are covered by the first shell layer, and forming a second shell layer covering the core.

Abstract: Provided are spin field effect logic devices, the logic devices including: a gate electrode; a channel formed of a magnetic material above the gate electrode to selectively transmit spin-polarized electrons; a source on the channel; and a drain and an output electrode on the channel outputting electrons transmitted from the source. The gate electrode may control a magnetization state of the channel in order to selectively transmit the electrons injected from the source to the channel.

Abstract: A semiconductor device may include a substrate having a drift region doped to a first conduction type. A trench may be etched into an upper surface of the substrate. A gate may be arranged along side walls of the trench. A gate oxide layer may be between the side walls of the trench and gate and between a bottom surface of the trench and gate. A first source region of the first conduction type may be on the upper surface of the substrate. A second source region of the first conduction type may be on the bottom surface of the trench. A first well region may be between the first source region and drift region, and a second well region may be between the second source region and drift region, the first and second well regions being doped to a second conduction type (electrically opposite to the first conduction type).

Abstract: According to example embodiments, a HEMT includes a channel layer, a channel supply layer on the channel layer, a source electrode and a drain electrode spaced apart on the channel layer, a depletion-forming layer on the channel supply layer, and a plurality of gate electrodes on the depletion-forming layer between the source electrode and the drain electrode. The channel supply layer is configured to induce a two-dimensional electron gas (2DEG) in the channel layer. The depletion-forming layer is configured to form a depletion region in the 2DEG. The plurality of gate electrodes include a first gate electrode and a second gate electrode spaced apart from each other.

Abstract: According to example embodiments, a high electron mobility transistor includes: a channel layer including a first semiconductor material; a channel supply layer on the channel layer and configured to generate a 2-dimensional electron gas (2DEG) in the channel layer, the channel supply layer including a second semiconductor material; source and drain electrodes spaced apart from each other on the channel layer, and an upper surface of the channel supply layer defining a gate electrode receiving part; a first gate electrode; and at least one second gate electrode spaced apart from the first gate electrode and in the gate electrode receiving part. The first gate electrode may be in the gate electrode receiving part and between the source electrode and the drain electrode. The at least one second gate electrode may be between the source electrode and the first gate electrode.

Abstract: According to example embodiments, a high electron mobility transistor (HEMT) includes a channel layer; a channel supply layer on the channel layer; a source electrode and a drain electrode spaced apart from each other on one of the channel layer and the channel supply layer; a gate electrode on a part of the channel supply layer between the source electrode and the drain electrode; a first depletion-forming layer between the gate electrode and the channel supply layer; and a at least one second depletion-forming layer on the channel supply layer between the gate electrode and the drain electrode. The at least one second depletion-forming layer is electrically connected to the source electrode.

Abstract: A method of packaging power devices at a wafer level is disclosed. The method includes preparing a wafer having a plurality of nitride power devices thereon, each of the plurality of nitride power devices having a plurality of electrodes thereon; forming a polymer layer on the plurality of nitride power devices; exposing each of the electrodes from the polymer layer; forming a solder bump on the exposed electrodes; forming a molding layer covering the solder bump on the polymer layer; and removing the wafer and exposing the solder bump.

Abstract: According to example embodiments, a HEMT includes a channel layer, a channel supply layer on the channel layer, a source electrode and a drain electrode spaced apart on the channel layer, a depletion-forming layer on the channel supply layer, and a plurality of gate electrodes on the depletion-forming layer between the source electrode and the drain electrode. The channel supply layer is configured to induce a two-dimensional electron gas (2DEG) in the channel layer. The depletion-forming layer is configured to form a depletion region in the 2DEG. The plurality of gate electrodes include a first gate electrode and a second gate electrode spaced apart from each other.

Abstract: A semiconductor device includes a drift layer including a trench formed on a semiconductor substrate. A well in the drift layer overlaps an edge of the trench, and at least one gate electrode is formed at this overlapping edge region. The drift layer and semiconductor may be doped with a first type of impurity and the well may be doped with a second type of impurity. Through this arrangement, an improved distribution of carriers may be formed in the drift layer.

Abstract: According to example embodiments, a HEMT includes a channel supply layer on a channel layer, a p-type semiconductor structure on the channel supply layer, a gate electrode on the p-type semiconductor structure, and source and drain electrodes spaced apart from two sides of the gate electrode respectively. The channel supply layer may have a higher energy bandgap than the channel layer. The p-type semiconductor structure may have an energy bandgap that is different than the channel supply layer. The p-type semiconductor structure may include a hole injection layer (HIL) on the channel supply layer and be configured to inject holes into at least one of the channel layer and the channel supply in an on state. The p-type semiconductor structure may include a depletion forming layer on part of the HIL. The depletion forming layer may have a dopant concentration that is different than the dopant concentration of the HIL.

Abstract: Example embodiments relate to semiconductor devices and/or methods of manufacturing the same. According to example embodiments, a semiconductor device may include a first heterojunction field effect transistor (HFET) on a first surface of a substrate, and a second HFET. A second surface of the substrate may be on the second HFET. The second HFET may have different properties (characteristics) than the first HFET. One of the first and second HFETs may be of an n type, while the other thereof may be of a p type. The first and second HFETs may be high-electron-mobility transistors (HEMTs). One of the first and second HFETs may have normally-on properties, while the other thereof may have normally-off properties.