摘要:
A method of fabricating a Schottky diode using gallium nitride (GaN) materials includes providing an n-type GaN substrate having a first surface and a second surface. The second surface opposes the first surface. The method also includes forming an ohmic metal contact electrically coupled to the first surface of the n-type GaN substrate and forming an n-type GaN epitaxial layer coupled to the second surface of the n-type GaN substrate. The method further includes forming an n-type aluminum gallium nitride (AlGaN) surface layer coupled to the n-type GaN epitaxial layer and forming a Schottky contact electrically coupled to the n-type AlGaN surface layer.
摘要:
A method for fabricating an edge termination structure includes providing a substrate having a first surface and a second surface and a first conductivity type, forming a first GaN epitaxial layer of the first conductivity type coupled to the first surface of the substrate, and forming a second GaN epitaxial layer of a second conductivity type opposite to the first conductivity type. The second GaN epitaxial layer is coupled to the first GaN epitaxial layer. The method also includes implanting ions into a first region of the second GaN epitaxial layer to electrically isolate a second region of the second GaN epitaxial layer from a third region of the second GaN epitaxial layer. The method further includes forming an active device coupled to the second region of the second GaN epitaxial layer and forming the edge termination structure coupled to the third region of the second GaN epitaxial layer.
摘要:
A semiconductor structure includes a III-nitride substrate with a first side and a second side opposing the first side. The III-nitride substrate is characterized by a first conductivity type and a first dopant concentration. The semiconductor structure also includes a III-nitride epitaxial layer of the first conductivity type coupled to the first surface of the III-nitride substrate, and a first metallic structure electrically coupled to the second surface of the III-nitride substrate. The semiconductor structure further includes an AlGaN epitaxial layer coupled to the III-nitride epitaxial layer of the first conductivity type, and a III-nitride epitaxial structure of a second conductivity type coupled to the AlGaN epitaxial layer. The III-nitride epitaxial structure comprises at least one edge termination structure.
摘要:
A method of forming a doped region in a III-nitride substrate includes providing the III-nitride substrate and forming a masking layer having a predetermined pattern and coupled to a portion of the III-nitride substrate. The III-nitride substrate is characterized by a first conductivity type and the predetermined pattern defines exposed regions of the III-nitride substrate. The method also includes heating the III-nitride substrate to a predetermined temperature and placing a dual-precursor gas adjacent the exposed regions of the III-nitride substrate. The dual-precursor gas includes a nitrogen source and a dopant source. The method further includes maintaining the predetermined temperature for a predetermined time period, forming p-type III-nitride regions adjacent the exposed regions of the III-nitride substrate, and removing the masking layer.
摘要:
A diode includes a substrate characterized by a first dislocation density and a first conductivity type, a first contact coupled to the substrate, and a masking layer having a predetermined thickness and coupled to the semiconductor substrate. The masking layer comprises a plurality of continuous sections and a plurality of openings exposing the substrate and disposed between the continuous sections. The diode also includes an epitaxial layer greater than 5 μm thick coupled to the substrate and the masking layer. The epitaxial layer comprises a first set of regions overlying the plurality of openings and characterized by a second dislocation density and a second set of regions overlying the set of continuous sections and characterized by a third dislocation density less than the first dislocation density and the second dislocation density. The diode further includes a second contact coupled to the epitaxial layer.
摘要:
A vertical III-nitride field effect transistor includes a drain comprising a first III-nitride material, a drain contact electrically coupled to the drain, and a drift region comprising a second III-nitride material coupled to the drain. The field effect transistor also includes a channel region comprising a third III-nitride material coupled to the drain and disposed adjacent to the drain along a vertical direction, a gate region at least partially surrounding the channel region, having a first surface coupled to the drift region and a second surface on a side of the gate region opposing the first surface, and a gate contact electrically coupled to the gate region. The field effect transistor further includes a source coupled to the channel region and a source contact electrically coupled to the source. The channel region is disposed between the drain and the source along the vertical direction such that current flow during operation of the vertical III-nitride field effect transistor is along the vertical direction, and the channel region extends along at least a portion of the second surface of the gate region.
摘要:
Apparatus and method for control of epitaxial growth parameters, for example during manufacture of light emitting diodes (LEDs). Embodiments include PL measurement of a group III-V film following growth while a substrate at an elevated temperature is in a transfer chamber of a multi-chamber cluster tool. In other embodiments, a film thickness measurement, a contactless resistivity measurement, and a particle and/or roughness measure is performed while the substrate is disposed in the transfer chamber. One or more of the measurements performed in the transfer chamber are temperature corrected to room temperature by estimating the elevated temperature based on emission from a GaN base layer disposed below the group III-V film. In other embodiments, temperature correction is based on an absorbance band edge of the GaN base layer determined from collected white light reflectance spectra. Temperature corrected metrology is then used to control growth processes.
摘要:
A method of texturing a surface within or immediately adjacent to a template layer of a LED is described. The method uses a texturing laser directed through a substrate to decompose and pit a semiconductor material at the surface to be textured. By texturing the surface, light trapping within the template layer is reduced. Furthermore, by patterning the arrangement of pits, metal coating each pit can be arranged to spread current through the template layer and thus through the n-doped region of a LED.
摘要:
Double well structures in electro-absorption modulators are created in quantum well active regions by embedding deep ultra thin quantum wells. The perturbation introduced by the embedded, deep ultra thin quantum well centered within a conventional quantum well lowers the confined energy state for the wavefunction in the surrounding larger well and typically results in the hole and electron distributions being more confined to the center of the conventional quantum well. The extinction ratio provided by the electro-absorption modulator is typically increased.
摘要:
A light emitting device in accordance with an embodiment of the present invention includes a first semiconductor layer of a first conductivity type having a first surface, and an active region formed overlying the first semiconductor layer. The active region includes a second semiconductor layer which is either a quantum well layer or a barrier layer. The second semiconductor layer is formed from a semiconductor alloy having a composition graded in a direction substantially perpendicular to the first surface of the first semiconductor layer. The light emitting device also includes a third semiconductor layer of a second conductivity type formed overlying the active region.