Abstract:
A storage node, phase change memory device having a storage node, a method of fabricating the phase change memory device and a method of operating the phase change memory device are provided. The phase change memory device includes a switching device and a storage node connecting to the switching device. The storage node includes a bottom electrode, a phase change layer formed on the bottom electrode, a material layer formed on the phase change layer and a top electrode formed on the phase change layer around the material layer.
Abstract:
A method of doping ions into an object using plasma, including providing a doping gas between a first electrode and a second electrode, where an object is disposed between the first and the second electrodes, applying a first power to the first electrode and grounding the second electrode, exciting the doping gas to a plasma state, directing ions toward the object to be doped, applying a second power to the second electrode and grounding the first electrode, and counting a dose of the ions directed toward the second electrode, and an apparatus for performing the same.
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 method of manufacturing a High Electron Mobility Transistor (HEMT) may include forming first and second material layers having different lattice constants on a substrate, forming a source, a drain, and a gate on the second material layer, and changing the second material layer between the gate and the drain into a different material layer, or changing a thickness of the second material layer, or forming a p-type semiconductor layer on the second material layer. The change in the second material layer may occur in an entire region of the second material layer between the gate and the drain, or only in a partial region of the second material layer adjacent to the gate. The p-type semiconductor layer may be formed on an entire top surface of the second material layer between the gate and the drain, or only on a partial region of the top surface adjacent to the gate.
Abstract:
High electron mobility transistors (HEMT) exhibiting dual depletion and methods of manufacturing the same. The HEMT includes a source electrode, a gate electrode and a drain electrode disposed on a plurality of semiconductor layers having different polarities. A dual depletion region exists between the source electrode and the drain electrode. The plurality of semiconductor layers includes an upper material layer, an intermediate material layer and a lower material layer, and a polarity of the intermediate material layer is different from polarities of the upper material layer and the lower material layer.
Abstract:
A phase change memory device includes a switching device and a storage node connected to the switching device. The storage node includes a bottom stack, a phase change layer disposed on the bottom stack and a top stack disposed on the phase change layer. The phase change layer includes a unit for increasing a path of current flowing through the phase change layer and reducing a volume of a phase change memory region. The area of a surface of the unit disposed opposite to the bottom stack is greater than or equal to the area of a surface of the bottom stack in contact with the phase change layer.
Abstract:
An electron cyclotron resonance equipment generates plasma by application of a processing gas and microwave energy into a vacuum chamber having a wafer therein in an environment of reduced pressure. The equipment includes a horn antenna assembly mounted onto an uppermost end of the vacuum chamber for radiating the microwave energy supplied from a high-frequency generator into the vacuum chamber. The horn antenna enables extension and retraction in a lengthwise direction to change a flare angle of the horn antenna. The equipment is provided with a fixed antenna and a plurality of mobile antennas to configure a horn antenna assembly, thereby enabling control of the flare angle in the horn antenna as a result of displacement of the mobile antennas. Thus, the uniformity in radiation of the microwave energy within plasma chamber can be controlled with efficiency.
Abstract:
An electron cyclotron resonance equipment generates plasma by application of a processing gas and microwave energy into a vacuum chamber having a wafer therein in an environment of reduced pressure. The equipment includes a horn antenna assembly mounted onto an uppermost end of the vacuum chamber for radiating the microwave energy supplied from a high-frequency generator into the vacuum chamber. The horn antenna enables extension and retraction in a lengthwise direction to change a flare angle of the horn antenna. The equipment is provided with a fixed antenna and a plurality of mobile antennas to configure a horn antenna assembly, thereby enabling control of the flare angle in the horn antenna as a result of displacement of the mobile antennas. Thus, the uniformity in radiation of the microwave energy within plasma chamber can be controlled with efficiency.