Liquid metal inclusion migration by means of an electrical potential gradient
AssigneeGeneral Electric Company
InventorThomas R. Anthony
Life of this patent
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Abstract
Liquid metal inclusions are migrated in a host body of semiconductor material by means of an electrical potential gradient to produce regions of recrystallized single crystal semiconductor material in the host body. The resistivities of the regions and the semiconductor material of the host body will be different and if the conductivity types of the regions and the semiconductor material of the host body are also different, P-N junctions will be formed between the regions and the host body.
Claims26
A method for migrating one or more liquid metal inclusions in a host body of single crystal semiconductor material by means of an electrical potential gradient to produce one or more regions of recrystallized single crystal semiconductor material in said host body of semiconductor material, said regions having at least a resistivity different from that of said host body of semiconductor material, comprising the steps of:
- (a) determining the direction said one or more liquid metal inclusions are to be migrated along one or more paths in said host body between anode and cathode connections;
- (b) depositing one or more solid metallic bodies in contact with said host body, the material of each said solid metallic body being selected such that the material of each said solid metallic body:
- (i) is soluble in the semiconductor material of said host body, and
- (ii) forms a solution with the semiconductor material of said host body, said solution having a melting temperature lower than the melting temperature of the semiconductor material of said host body, and
- (iii) has a work function, .phi..sub.i, such that the quantity (.phi..sub.i -.phi..sub.h), where .phi..sub.h is the work function of the semiconductor material of said host body, has the same algebraic sign as the connection toward which said one or more inclusions are to be migrated;
- (c) applying said anode and cathode connections to said host body;
- (d) heating said host body to an elevated temperature, said elevated temperature being substantially constant and uniform throughout said host body and sufficient to melt said one or more solid metallic bodies forming thereby one or more liquid metal inclusions;
- (e) applying said electrical potential gradient between said anode and cathode connections;
- and
- (f) migrating by means of said electrical potential gradient said one or more liquid metal inclusions in said host body along said path or paths forming thereby one or more regions of recrystallized single crystal semiconductor material integral with said host body, each said region of recrystallized single crystal semiconductor material comprising the material of the liquid metal inclusion which formed said region in solid solution up to the solid solubility limit of the material of said liquid metal inclusion in the semiconductor material of said host body and having at least a resistivity different from that of the semiconductor material of said host body.
A method for migrating one or more liquid metal inclusions in a host thin film of single crystal semiconductor material by means of an electrical potential gradient to produce one or more regions of recrystallized single crystal semiconductor material in said host thin film of semiconductor material, said regions having at least a resistivity different from that of said host thin film of semiconductor material, said thin film being situated on and conforming with at least a portion of a surface of an underlying substrate body, comprising the steps of:
- (a) determining the direction said one or more liquid metal inclusions are to be migrated along one or more paths in said host thin film between anode and cathode connections;
- (b) depositing one or more solid metallic bodies in contact with said host thin film, the material of each said solid metallic body being selected such that the material of each said solid metallic body;
- (i) is soluble in the semiconductor material of said host thin film, and
- (ii) forms a solution with the semiconductor material of said host thin film, said solution having a melting temperature lower than the melting temperature of the semiconductor material of said host thin film, and
- (iii) has a work function, .phi..sub.i, such that the quantity (.phi..sub.i -.phi..sub.h), where .phi..sub.h is the work function of the semiconductor material of said host thin film, has the same algebraic sign as the connection toward which said one or more inclusions are to be migrated;
- (c) applying said anode and cathode connections to said host thin film;
- (d) heating said host thin film to an elevated temperature, said elevated temperature being substantially constant and uniform throughout said host thin film and sufficient to melt said one or more solid metallic bodies forming thereby one or more liquid metal inclusions;
- (e) applying said electrical potential gradient between said anode and cathode connections;
- and
- (f) migrating by means of said electrical potential gradient said one or more liquid metal inclusions in said host thin film along said path or paths forming thereby one or more regions of recrystallized single crystal semiconductor material integral with said host thin film, each said region of recrystallized single crystal semiconductor material comprising the material of the liquid metal inclusion which formed said region in said solution up to the solid solubility limit of the material of said liquid metal inclusion in the semiconductor material of said host thin film and having at least a resisitivity different from that of the semiconductor material of said host thin film.
A method for migrating one or more liquid metal inclusions in a host thin film of single crystal semiconductor material by means of thermal and electrical potential gradients to produce one or more regions of recrystallized single crystal semiconductor material in said host thin film of semiconductor material, said regions having at least a resistivity different from that of said host thin film of semiconductor material, said thin film being situated on and conforming with at least a portion of a surface of an underlying substrate body, comprising the steps of:
- (a) determining the direction said one or more liquid metal inclusions are to be migrated along one or more paths in said host thin film between anode and cathode connections;
- (b) depositing one or more solid metallic bodies in contact with said host thin film, the material of each said solid metallic body being selected such that the material of each said solid metallic body:
- (i) is soluble in the semiconductor material of said host thin film, and
- (ii) forms a solution with the semiconductor material of said host thin film, said solution having a melting temperature lower than the melting temperature of the semiconductor material of said host thin film, and
- (iii) has a work function, .phi..sub.i, such that the quantity (.phi..sub.i -.phi..sub.h), where .phi..sub.h is the work function of the semiconductor material of said host thin film, has the same algebraic sign as the connection toward which said one or more inclusions are to be migrated;
- (c) applying said anode and cathode connections to said host thin film;
- (d) establishing and maintaining a finite temperature gradient through said host thin film and said substrate, the temperature of the uppermost surface of said thin film being lower than the temperature of the bottommost surface of said substrate, the temperatures in said gradient through said thin film being above the melting temperature of said one or more solid metallic bodies forming thereby one or more liquid metal inclusions extending through the thickness of said thin film;
- (e) applying said electrical potential gradient between said anode and cathode connections, said electrical gradient being substantially perpendicular to the thickness of said thin film and being substantially perpendicular to said finite temperature gradient;
- and
- (f) migrating by means of said electrical potential gradient said one or more liquid metal inclusions in said host thin film along said path or paths forming thereby one or more regions of recrystallized single crystal semiconductor material integral with said host thin film, each said region of recrystallized single crystal semiconductor material comprising the material of the liquid metal inclusion which formed said region in solid solution up to the solid solubility limit of the material of said liquid metal inclusion in the semiconductor material of said host thin film and having at least a resistivity different from that of the semiconductor material of said host thin film.
Dependencies are inferred from the claim text.