Superlattice structure and method for making the same
AssigneeSensor Electronic Technology, Inc.
InventorsMichael Shur, Remigijus Gaska, Jinwei Yang
Life of this patent
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Abstract
A superlattice layer including a plurality of periods, each of which is formed from a plurality of sub-layers is provided. Each sub-layer comprises a different composition than the adjacent sub-layer(s) and comprises a polarization that is opposite a polarization of the adjacent sub-layer(s). In this manner, the polarizations of the respective adjacent sub-layers compensate for one another. Furthermore, the superlattice layer can be configured to be at least partially transparent to radiation, such as ultraviolet radiation.
Claims20
A structure comprising:
- a first layer;
- and
- a superlattice layer having a first side adjacent to the first layer, the superlattice layer including a plurality of periods, each of the plurality of periods including:
- a first sub-layer having a first composition and a first net polarization;
- and
- a second sub-layer adjacent to the first sub-layer, the second sub-layer having a second composition distinct from the first composition and a second net polarization opposite the first net polarization, wherein each net polarization is calculated using a spontaneous polarization and a strain-induced polarization for the corresponding sub-layer, and wherein an absolute value of the first net polarization is substantially equal to an absolute value of the second net polarization.
A method comprising:
- creating a structure design for a device, the structure design including a first layer and a superlattice layer having a first side adjacent to the first layer, the superlattice layer comprising a plurality of periods, the creating the structure design including:
- selecting a first composition having a first net polarization for a first sub-layer of each of the plurality of periods;
- and
- selecting a second composition having a second net polarization for a second sub-layer of each of the plurality of periods, wherein the second sub-layer is adjacent to the first sub-layer, and wherein the second composition is distinct from the first composition and the second net polarization is opposite the first net polarization, wherein each net polarization is calculated using a spontaneous polarization and a strain-induced polarization for the corresponding sub-layer, and wherein an absolute value of the first net polarization is substantially equal to an absolute value of the second net polarization.
A group III nitride-based device comprising:
- a p-type contact comprising:
- a first p-type layer;
- and
- a p-type superlattice layer including a plurality of periods, each of the plurality of periods including:
- a first sub-layer having a first group III nitride-based composition and a first net polarization;
- and
- a second sub-layer adjacent to the first sub-layer, the second sub-layer having a second group III nitride-based composition distinct from the first composition and a second net polarization opposite the first net polarization, wherein the first net polarization and the second net polarization comprise at least one of:
- a strain-induced polarization or a spontaneous polarization, wherein each net polarization is calculated using a spontaneous polarization and a strain-induced polarization for the corresponding sub-layer, and wherein an absolute value of the first net polarization is substantially equal to an absolute value of the second net polarization.
Dependencies are inferred from the claim text.