METHODS OF SPATIALLY IMPLANTING SPECIES IN III-NITRIDE SEMICONDUCTOR STRUCTURES
III-nitride materials are generally described herein, including material structures comprising III-nitride material regions and silicon-containing substrates. Certain embodiments are related to gallium nitride materials and material structures comprising gallium nitride material regions and silicon-containing substrates.
1 . A method of forming a semiconductor structure, comprising:
implanting a species into a surface region of a substrate comprising silicon such that the implanted species forms a pattern spatially defined across at least one lateral dimension of the substrate and the surface regions of the substrate in which the species are implanted comprise a low-conductivity parasitic channel or are free of a parasitic channel and the surface regions of the substrate in which the species are not implanted comprise a parasitic channel, wherein:
during the implanting step, at least a portion of the species is implanted through a III-nitride material region, and
after the implanting step, the implanted species is present within at least a portion of the surface region of the substrate at a concentration of at least about 10 19 /cm 3 ; and
the surface regions of the substrate that comprise a parasitic channel are laterally spatially separated from one another by the surface regions of the substrate that comprise a low-conductivity parasitic channel or that are free of a parasitic channel.
2 . The method of claim 1 , wherein the semiconductor structure comprises a transistor located over the substrate.
3 . The method of claim 2 , wherein, after the implanting step, at least a portion of the substrate underneath a channel between a source of the transistor and a drain of the transistor is substantially free of the implanted species.
4 . The method of claim 1 , wherein the semiconductor structure comprises a second transistor laterally spaced apart from the first transistor, and wherein, after the implanting step, a portion of the surface region of the substrate between the first transistor and the second transistor has a concentration of the implanted species of at least about 10 19 /cm 3 .
5 . The method of claim 1 , wherein the III-nitride material region comprises a 2DEG region, and, after the implanting step, the 2DEG region is substantially free of the implanted species.
6 . The method of claim 1 , wherein the substrate comprises at least a layer having a resistivity of greater than about 10 2 Ohms-cm.
7 . The method of claim 1 , wherein the substrate is a silicon substrate.
8 . The method of claim 7 , wherein the substrate is a bulk silicon wafer.
9 . The method of claim 7 , wherein the substrate is a silicon-on-insulator substrate.
10 . The method of claim 1 , wherein the substrate is a silicon carbide substrate.
11 . The method of claim 1 , wherein the III-nitride material region comprises GaN.
12 . The method of claim 1 , wherein the III-nitride material region comprises a III-nitride nucleation layer.
13 . The method of claim 1 , wherein the III-nitride material region comprises a III-nitride transition layer.
14 . The method of claim 13 , wherein the III-nitride transition layer is compositionally graded.
15 . The method of claim 1 , wherein the III-nitride material region comprises a III-nitride buffer layer.
16 . The method of claim 1 , wherein the III-nitride material region comprises a III-nitride device region.
17 . The method of claim 1 , wherein a diffusion barrier region is located between the III-nitride material region and the substrate.
18 - 21 . (canceled)