Methods for making silicon-on-insulator structures

A method of making semiconductor-on-insulator structures, which comprises:

• forming first and second semiconductor protrusions which are attached to a substrate;
• bonding portions of the first and second protrusions to an insulative surface;
• and
• reducing the temperature of the first and second protrusions to break at least one of the protrusions into at least two portions, with one of the two portions being bonded to the surface, wherein the substrate and the insulative surface have different thermal-expansion coefficients.

A method of making an integrated circuit having semiconductor-on-insulator structures, which comprises:

• attaching two or more semiconductive structures to an insulative surface;
• forming one or more transistors from the semiconductive structures;
• forming two or more semiconductive protrusions integral to a semiconductive substrate;
• placing the two or more semiconductive protrusions in contact with the insulative surface;
• and
• thermally expanding or contracting a semiconductive material underlying the insulative surface to break each of the protrusions into at least two portions, wherein at least one of the two portions are bonded to the insulative surface.

A method of making semiconductor-on-insulator structures, which comprises:

• forming two or more semiconductive structures attached to a substrate;
• attaching the two or more semiconductive structures to an insulative surface;
• and
• thermally expanding or contracting a semiconductive material underlying the insulative surface to break at least one of the protrusions into at least two portions, wherein at least one of the two portions is bonded to the insulative surface.

A method of making semiconductor-on-insulator structures, which comprises:

• forming two or more semiconductive structures attached to a substrate;
• attaching the two or more semiconductive structures to an insulative surface;
• and
• thermally expanding or contracting a semiconductive material underlying the insulative surface to break at least one of the protrusions into at least two portions, wherein at least one of the two portions is bonded to the insulative surface, wherein the substrate and the insulative surface have different thermal-expansion coefficients.

A method of making an integrated circuit, which comprises:

• forming two or more semiconductive structures;
• attaching the two or more semiconductive structures to an insulative surface;
• and
• thermally expanding or contracting a semiconductive material underlying the insulative surface to separate at least a portion of at least one of the semiconductive structures from the substrate.

A method of making semiconductor-on-insulator structures, which comprises:

• forming first and second semiconductive protrusions which are attached to a substrate;
• attaching portions of the first and second protrusions to an insulative surface;
• and
• thermally expanding or contracting the substrate and portions of the first and second protrusions to break at least one of the protrusions into at least two portions, with one of the two portions being bonded to the insulative surface.

A method of making semiconductor-on-insulator structures, which comprises:

• forming first and second semiconductive protrusions which are attached to a substrate;
• attaching portions of the first and second protrusions to an insulative surface;
• and
• thermally expanding or contracting the substrate and portions of the first and second protrusions to break at least one of the protrusions into at least two portions, with one of the two portions being bonded to the insulative surface, wherein the substrate and the insulative surface have different thermal-expansion coefficients.

A method of making semiconductor-on-insulator structures, which comprises:

• forming at least a first and second semiconductor protrusions which are attached to a substrate, wherein each semiconductor protrusion has a top;
• partially undercutting the first and second semiconductor protrusions to form respective first and second base portions each narrower than its corresponding semiconductive protrusion top;
• bonding the first and second protrusion tops to an insulative surface;
• thermally expanding or contracting the insulative surface;
• and
• separating at least a portion of each semiconductive structure from the substrate.

A method of making semiconductor-on-insulator structures, which comprises:

• forming first and second semiconductor protrusions which are attached to a silicon substrate, wherein forming the first and second protrusions comprises:
• forming first and second elevated areas in the silicon substrate layer, each elevated area having a top;
• and
• partially undercutting the first and second elevated areas to form respective first and second base portions each narrower than its top;
• bonding the top of each elevated area to an insulative surface;
• reducing the temperature of the first and second protrusions to break at least one of the protrusions into at least two portions, with one of the two portions being bonded to the surface.

A method of making semiconductor-on-insulator structures, which comprises:

• forming first and second semiconductive protrusions which are attached to a substrate;
• bonding portions of the first and second protrusions to an insulative surface;
• forming a thermally-activatable cleavage plane through the first and second protrusions, wherein forming the thermally-activatable cleavage plane comprises implanting ions into the first and second protrusions;
• and
• heating the protrusions to activate the plane and divide each of the protrusions into at least two portions, with one of the two portions being bonded to the insulative surface.

A method of making semiconductor-on-insulator structures, which comprises:

• forming first and second semiconductive protrusions which are attached to a substrate;
• bonding portions of the first and second protrusions to an insulative surface;
• implanting ions into the first and second protrusions to form a thermally-activatable cleavage plane through the first and second protrusions;
• and
• activating the thermally-activatable cleavage plane to divide each of the protrusions into at least two portions, with one of the two portions being bonded to the insulative surface.

A method of making semiconductor-on-insulator structures, which comprises:

• forming first and second semiconductive protrusions which are attached to a substrate;
• forming a thermally-activatable cleavage plane through the first and second protrusions;
• bonding portions of the first and second protrusions to an insulative surface;
• and
• heating the protrusions to activate the thermally-activatable cleavage plane to divide each of the protrusions into at least two portions, with one of the two portions being bonded to the insulative surface.