Stress mitigating amorphous SiO2 interlayer

A method of forming a REO dielectric layer and a layer of amorphous silicon oxide between a layer of III-N semiconductor material and a silicon substrate, the method comprising the steps of:

• providing a crystalline silicon substrate;
• depositing a first layer of single crystal rare earth oxide on the silicon substrate, the first layer of single crystal rare earth oxide having a first lattice constant adjacent the silicon substrate approximately matching the lattice constant of the silicon substrate, and adjusting the lattice constant of the first layer of rare earth oxide adjacent an upper surface of the first layer of rare earth oxide to approximately a lattice constant of a selected III-N material;
• depositing a uniform layer of amorphous silicon on the first layer of rare earth oxide;
• depositing a second layer of rare earth oxide on the layer of amorphous silicon, the step of depositing the second layer of rare earth oxide including ramping the temperature of the substrate to a temperature required for epitaxial growth and epitaxially growing the second layer of rare earth oxide, the temperature required for epitaxial growth crystallizing the layer of amorphous silicon to form a layer of crystallized silicon and the crystallized silicon transferring the adjusted lattice constant of the first layer of rare earth oxide to the second layer of rare earth oxide;
• and oxidizing the crystalline silicon to transform the crystalline silicon to amorphous silicon oxide including raising the temperature of the substrate to a temperature above the temperature required for epitaxial growth and performing the raising in an oxygen atmosphere;
• and epitaxially growing a single crystal layer of the selected III-N material on the second layer of rare earth oxide.

A method of forming a REO dielectric layer and a layer of amorphous silicon oxide between a layer of III-N semiconductor material and a silicon substrate, the method comprising the steps of:

• providing a crystalline silicon substrate;
• depositing a first layer of single crystal rare earth oxide on the silicon substrate, the first layer of single crystal rare earth oxide having a first lattice constant adjacent the silicon substrate approximately matching the lattice constant of the silicon substrate, and adjusting the lattice constant of the first layer of rare earth oxide adjacent an upper surface of the first layer of rare earth oxide to approximately a lattice constant of a selected III-N material;
• depositing a uniform layer of amorphous silicon on the first layer of rare earth oxide;
• depositing a second layer of rare earth oxide on the layer of amorphous silicon, the step of depositing the second layer of rare earth oxide including ramping the temperature of the substrate to a temperature required for epitaxial growth and epitaxially growing the second layer of rare earth oxide, the temperature required for epitaxial growth crystallizing the layer of amorphous silicon to form a layer of crystallized silicon and the crystallized silicon transferring the adjusted lattice constant of the first layer of rare earth oxide to the second layer of rare earth oxide;
• and oxidizing the crystalline silicon to transform the crystalline silicon to amorphous silicon oxide including epitaxially growing a single crystal layer of the selected III-N material on the second layer of rare earth oxide, the epitaxially growing of the single crystal layer of the selected III-N material including raising the temperature of the substrate to a temperature of 1100° C. or less.