Heterostructure with carrier concentration enhanced by single crystal REO induced strains

A heterostructure on a silicon substrate comprising:

• a single crystal silicon substrate;
• a single crystal rare earth oxide template positioned on the silicon substrate, the template being substantially crystal lattice matched to the surface of the silicon substrate;
• a III-N layer positioned on the surface of the template, the III-N layer being crystal lattice matched to the template so as to reduce stress/strain in the III-N layer;
• a barrier layer of single crystal III-III-N material grown on the upper surface of the III-N layer and defining an interface between the III-N layer and the III-III-N layer, the single crystal III-N material having a larger lattice constant than the III-III-N layer and defining a heterojunction with 2DEG at the interface;
• and
• a single crystal rare earth oxide dielectric layer grown on the active layer of III-III-N material so as to induce compressive stress in the rare earth oxide layer and tensile strain in the III-III-N layer, the tensile strain in the III-III-N layer and the compressive stress in the rare earth oxide layer combining to induce a piezoelectric field leading to higher carrier concentration at the heterojunction.

A method of growing heterostructure on a silicon substrate comprising the steps of:

• Providing a single crystal silicon substrate;
• growing or depositing a single crystal rare earth oxide template on the silicon substrate, the template being substantially crystal lattice matched to the surface of the silicon substrate;
• growing or depositing a heterostructure on the template, the heterostructure defining at least one heterojunction at an interface between a III-N layer and a III-III-N layer, the template and the heterostructure being crystal matched to reduce stress/strain in the heterostructure;
• and
• growing or depositing a single crystal rare earth oxide dielectric layer on the heterostructure so as to induce compressive stress in the rare earth oxide dielectric layer tensile strain at the at least one heterojunction, the tensile strain being induced in the III-III-N layer, and the compressive stress in the rare earth oxide dielectric layer combining with the tensile strain in the III-III-N layer to induce a piezoelectric field leading to higher carrier concentration at the heterojunction.

A method of growing a heterostructure on a silicon substrate comprising the steps of:

• providing a single crystal silicon substrate;
• growing or depositing a single crystal rare earth oxide template on the silicon substrate, the template being substantially crystal lattice matched to the surface of the silicon substrate;
• growing or depositing a single crystal III-N layer on the surface of the template, the III-N layer being crystal lattice matched to the template so as to reduce stress/strain in the III-N layer;
• growing or depositing a barrier layer of single crystal III-III-N material on the upper surface of the III-N layer and defining an interface between the III-N layer and the III-III-N layer, and the single crystal III-N material having a larger lattice constant than the III-III-N layer to define a heterojunction with 2DEG at the interface;
• and
• growing or depositing a single crystal rare earth oxide dielectric layer on the barrier layer of III-III-N material inducing compressive stress in the single crystal rare earth oxide dielectric layer and tensile strain in the III-III-N layer and the compressive stress in the III-III-N layer, the compressive stress and tensile strain combining to induce a piezoelectric field leading to higher carrier concentration at the heterojunction.