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 power device includes a switching device having a control terminal and an output terminal; and a driving circuit configured to provide a driving voltage to the control terminal such that a voltage between the control terminal and the output terminal remains less than or equal to a critical voltage. A rise time required for the driving voltage to reach a target level is determined according to current-voltage characteristics of the switching device. And, when the voltage between the control terminal and the output terminal exceeds the critical voltage, leakage current is generated between the control terminal and the output terminal.

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: A high electron mobility transistor (HEMT) according to example embodiments includes a first semiconductor layer, a second semiconductor layer on the first semiconductor layer, and a reverse diode gate structure on the second semiconductor layer. A source and a drain may be on at least one of the first semiconductor layer and the second semiconductor layer. A gate electrode may be on the reverse diode gate structure.

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: 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.

Abstract: A nitride semiconductor based power converting device includes a nitride semiconductor based power transistor, and at least one nitride semiconductor based passive device. The passive device and the power transistor respectively include a channel layer including a first nitride semiconductor material, and a channel supply layer on the channel layer including a second nitride semiconductor material to induce a 2-dimensional electron gas (2DEG) at the channel layer. The passive device may be a resistor, an inductor, or a capacitor.

Abstract: A semiconductor device includes a first compound semiconductor layer on a substrate, first through third electrodes spaced apart from each other on the first compound semiconductor layer, a second compound semiconductor layer on the first compound semiconductor layer between the first through third electrodes, a third compound semiconductor layer on the second compound semiconductor layer between the first and second electrodes, a first gate electrode on the third compound semiconductor layer, a fourth compound semiconductor layer having a smaller thickness than the third compound semiconductor layer on a portion of the second compound semiconductor layer between the second and third electrodes, and a second gate electrode on the fourth compound semiconductor layer. The first compound semiconductor layer between the second and third electrodes includes a 2-dimensional electron gas (2DEG) and the third compound semiconductor layer includes a 2-dimensional hole gas (2DHG).

Abstract: According to example embodiments, a normally-off high electron mobility transistor (HEMT) includes: a channel layer having a first nitride semiconductor, a channel supply layer on the channel layer, a source electrode and a drain electrode at sides of the channel supply layer, a depletion-forming layer on the channel supply layer, a gate insulating layer on the depletion-forming layer, and a gate electrode on the gate insulation layer. The channel supply layer includes a second nitride semiconductor and is configured to induce a two-dimensional electron gas (2DEG) in the channel layer. The depletion-forming layer is configured has at least two thicknesses and is configured to form a depletion region in at least a partial region of the 2DEG. The gate electrode contacts the depletion-forming layer.

Abstract: A power switching device includes a channel forming layer on a substrate which includes a 2-dimensional electron gas (2DEG), and a channel supply layer which corresponds to the 2DEG at the channel forming layer. A cathode is coupled to a first end of the channel supply layer and an anode is coupled to a second end of the channel supply layer. The channel forming layer further includes a plurality of depletion areas arranged in a pattern, and portions of the channel forming layer between the plurality of depletion areas are non-depletion areas.

Abstract: An electronic device may include a first transistor having a normally-on characteristic; a second transistor connected to the first transistor and having a normally-off characteristic; a constant voltage application unit configured to apply a constant voltage to a gate of the first transistor; and a switching unit configured to apply a switching signal to the second transistor. The first transistor may be a high electron mobility transistor (HEMT). The second transistor may be a field-effect transistor (FET). The constant voltage application unit may include a diode connected to the gate of the first transistor; and a constant current source connected to the diode.

Abstract: According to example embodiments, a high electron mobility transistor (HEMT) includes a channel supply layer that induces a two-dimensional electron gas (2DEG) in a channel layer, a source electrode and a drain electrode that are at sides of the channel supply layer, a depletion-forming layer that is on the channel supply layer and contacts the source electrode, a gate insulating layer on the depletion-forming layer, and a gate electrode on the gate insulating layer. The depletion-forming layer forms a depletion region in the 2DEG.

Abstract: According to example embodiments, a high electron mobility transistor includes: a channel layer including a 2-dimensional electron gas (2DEG); a contact layer on the channel layer; a channel supply layer on the contact layer; a gate electrode on a portion of the channel layer; and source and drain electrodes on at least one of the channel layer, the contact layer, and the channel supply layer. The contact layer is configured to form an ohmic contact on the channel layer. The contact layer is n-type doped and contains a Group III-V compound semiconductor. The source electrode and the drain electrode are spaced apart from opposite sides of the gate electrode.

Abstract: A higher electron mobility transistor (HEMT) and a method of manufacturing the same are disclosed. According to example embodiments, the HEMT may include a channel supply layer on a channel layer, a source electrode and a drain electrode that are on at least one of the channel layer and the channel supply layer, a gate electrode between the source electrode and the drain electrode, and a source pad and a drain pad. The source pad and a drain pad electrically contact the source electrode and the drain electrode, respectively. At least a portion of at least one of the source pad and the drain pad extends into a corresponding one of the source electrode and drain electrode that the at least one of the source pad and the drain pad is in electrical contact therewith.