Capping technique for zone-melting recrystallization of insulated semiconductor films

Claim 1

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said reactive material being reactive nitrogen, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 2

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said reactive material being reactive nitrogen, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 3

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said noninert gas being selected from the group consisting of ammonia and alkyl amines, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 4

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said noninert gas being selected from the group consisting of ammonia and alkyl amines, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 5

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 6

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 7

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noinert gas decomposing below the melting point of silicon to release said reactive material, said reactive material being reactive nitrogen, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, said annealing step being performed in two stages with an intervening oxidation step, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 8

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noinert gas decomposing below the melting point of silicon to release said reactive material, said reactive material being reactive nitrogen, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, said annealing step being performed in two stages with an intervening oxidation step, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 9

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said noninert gas being selected from the group consisting of ammonia and alkyl amines, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, said annealing step being performed in two stages with an intervening oxidation step, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 10

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said noninert gas being selected from the group consisting of ammonia and alkyl amines, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, said annealing step being performed in two stages with an intervening oxidation step, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 11

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, said annealing step being performed in two stages with an intervening oxidation step, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 12

A method of forming an encapsulated insulated semiconductor film structure, comprising forming a first layer of insulating material on a substrate, forming a second layer of amorphous or polycrystalline silicon, forming a third layer of silicon dioxide to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a sufficient length of time to diffuse quantities of said reactive material through the third layer to the interface with the second layer in an amount sufficient to avoid agglomeration of the resulting semiconductor film, said annealing step being performed in two stages with an intervening oxidation step, and subjecting the annealed structure resulting from the preceding steps to zone melting recrystallization.

Claim 15

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said reactive material being reactive nitrogen, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 16

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said reactive material being reactive nitrogen, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 17

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said noninert gas being selected from the group consisting of ammonia and alkyl amines, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 18

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said noninert gas being selected from the group consisting of ammonia and alkyl amines, annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 19

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 20

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 21

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 and N 2 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 22

A method of forming an encapsulated insulated semiconductor film body, comprising forming an insulating layer on a substrate, forming a semiconductor layer of amorphous or polycrystalline silicon on top of the insulating layer, forming a capping layer of silicon dioxide on top of the semiconductor layer to a partial thickness to form a silicon dioxide capped silicon on insulator structure, providing an atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide, said noninert gas decomposing below the melting point of silicon to release said reactive material, said atmosphere containing NH 3 and N 2 , annealing said structure in said atmosphere at a temperature below the melting point of silicon but high enough to decompose said gas so as to release said reactive material for a length of time sufficient for the reactive material to diffuse through the partial thickness of the capping layer to the interface with the semiconductor layer to avoid agglomeration of the resulting semiconductor film, increasing the thickness of the capping layer by forming an additional integral layer of the same material, and subjecting the structure formed by the preceding steps to zone-melting recrystallization.

Claim 24

A method of making an encapsulated silicon on insulator structure, comprising forming an encapsulated silicon on insulator structure having a silicon dioxide cap over an amorphous or polycrystalline silicon film, with a quantity of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide at the interface of the cap and film to avoid agglomeration of the film due to zone-melting recrystallization, by subjecting said structure, during formation before zone-melting recrystallization, to an annealing atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of said reactive material, said atmosphere being heated to a temperature below the melting point of silicon but sufficiently high to cause the noninert gas to decompose and release said reactive material in nascent, unbound form, said noninert gas being selected from the group consisting of ammonia and alkyl amines, and subjecting the resulting structure to zone-melting recrystallization.

Claim 25

A method of making an encapsulated silicon on insulator structure, comprising forming an encapsulated silicon on insulator structure having a silicon dioxide cap over an amorphous or polycrystalline silicon film, with a quantity of a reactive material whose presence promotes wetting of molten silicon on silicon dioxide at the interface of the cap and film to avoid agglomeration of the film due to zone-melting recrystallization, by subjecting said structure, during formation before zone-melting recrystallization, to an annealing atmosphere consisting essentially of inerts and a noninert gas, stable at ambient temperature, which is a source of said reactive material, said atmosphere being heated to a temperature below the melting point of silicon but sufficiently high to cause the noninert gas to decompose and release said reactive material in nascent, unbound form, said noninert gas being selected from the group consisting of ammonia and alkyl amines, and subjecting the resulting structure to zone-melting recrystallization.