US3879235A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of growing from solution materials exhibiting a peltier effect at the solid-melt interface
Assignee: Massachusetts Institute of Technology
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Filing: 1973-06-11
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Granted: 1975-04-22
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Expires: 1993-06-11
Abstract
Abstract A method of growing epitaxial layers from a solution in a solution-substrate system. An electrically conductive solution, consisting of one or more materials to be deposited upon the substrate, is placed in contact with the substrate. The temperature of the system is established and maintained at a level at which the solution is at or near saturation. An electric current is then passed across the interface between the solution and the substrate, the direction and magnitude of the current being chosen to effect cooling at the interface only, the remainder of the system being maintained at said equilibrium temperature.
Inventors
- 👤 Harry C Gatos
- 👤 August F Witt
- 👤 Manfred Lichtensteiger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:23
CPC Classifications
C; C30; C30B; C30B19/00; C30B19/10; C30B19/103; Y; Y10; Y10S; Y10S438/00; Y10S438/936
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
168 words
A METHOD OF GROWING EPITAXIAL LAYERS FROM A SOLUTION IN A SOLUTION-SUBSTRATE SYSTEM, SAID SYSTEM COMPRISING MATERIALS THAT EXHIBIT PELTIER EFFECT AT INTERFACE BETWEEN THE SOLUTION AND THE SUBSTRATE, THAT COMPRISES: PLACING A CONDUCTIVE SUBSTRATE IN CONTACT WITH A CONDUCTIVE SOLUTION WHICH INITIALLY COMPRISES A SOLVENT AND ONE OR MORE MATERIALS TO BE DEPOSITED UPON THE SUBSTRATE, EST ABLISHING AND MAINTAINING THE SOLUTION AND THE SUBSTRATE AT A TEMPERATURE AT WHICH SOLUTION IS LIQUID AND IS AT OR NEAR SATURATION, PASSING AN ELECTRIC CURRENT ACROSS THE SOLUTION-SUBSTRATE SYSTEM IN SUCH A WAY THAT COOLING IS EFFECTED AT THE INTERFACE BETWEEN THE LIQUID SOLUTION AND THE SUBSTRATE, SAID COOLING OCCURING ONLY DURING THE TIME WHICH ELECTRIC CURRENT FLOWS ACROSS THE INTERFACE AND ONLY AT THE REGION OF SAID INTERFACE, THE REST OF THE SOLUTION-SUBSTRATE SYSTEM, EXCEPT SAID INTERFACE, BEING MAINTAINED AT THE TEMPERATURE THAT EXISTED PRIOR TO THE PASSAGE OF THE ELECTRIC CURRENT, AND CONTROLLING THE MAGNITUDE OF THE ELECTRIC CURRENT TO CONTROL THE CURRENT DENSITY AT SAID INTERFACE.
Claim 2
Independent Claim
168 words
A METHOD OF GROWING EPITAXIAL LAYERS FROM A SOLUTION IN A SOLUTION-SUBSTRATE SYSTEM, SAID SYSTEM COMPRISING MATERIALS THAT EXHIBIT PELTIER EFFECT AT INTERFACE BETWEEN THE SOLUTION AND THE SUBSTRATE, THAT COMPRISES: PLACING A CONDUCTIVE SUBSTRATE IN CONTACT WITH A CONDUCTIVE SOLUTION WHICH INITIALLY COMPRISES A SOLVENT AND ONE OR MORE MATERIALS TO BE DEPOSITED UPON THE SUBSTRATE, EST ABLISHING AND MAINTAINING THE SOLUTION AND THE SUBSTRATE AT A TEMPERATURE AT WHICH SOLUTION IS LIQUID AND IS AT OR NEAR SATURATION, PASSING AN ELECTRIC CURRENT ACROSS THE SOLUTION-SUBSTRATE SYSTEM IN SUCH A WAY THAT COOLING IS EFFECTED AT THE INTERFACE BETWEEN THE LIQUID SOLUTION AND THE SUBSTRATE, SAID COOLING OCCURING ONLY DURING THE TIME WHICH ELECTRIC CURRENT FLOWS ACROSS THE INTERFACE AND ONLY AT THE REGION OF SAID INTERFACE, THE REST OF THE SOLUTION-SUBSTRATE SYSTEM, EXCEPT SAID INTERFACE, BEING MAINTAINED AT THE TEMPERATURE THAT EXISTED PRIOR TO THE PASSAGE OF THE ELECTRIC CURRENT, AND CONTROLLING THE MAGNITUDE OF THE ELECTRIC CURRENT TO CONTROL THE CURRENT DENSITY AT SAID INTERFACE.
Claim 3
Independent Claim
169 words
A method of growing epitaxial layers from a solution in a solution-substrate system, said system comprising materials that exhibit Peltier effect at interface between the solution and the substrate, that comprises: placing a conductive substrate in contact with a conductive solution which initially comprises a solvent and one or more materials to be deposited upon the substrate, establishing and maintaining the solution and the substrate at a temperature at which the solution is liquid and is at or near saturation, passing an electric current across the solution-substrate system in such a way that cooling is effected at the interface between the liquid solution and the substrate, said cooling occurring only during the time in which electric current flows across the interface and only at the region of said interface, the rest of the solution-substrate system, except said interface, being maintained at the temperature that existed prior to the passage of the electric current, and controlling the magnitude of the electric current to control the current density at said interface.
Claim 4
Independent Claim
169 words
A method of growing epitaxial layers from a solution in a solution-substrate system, said system comprising materials that exhibit Peltier effect at interface between the solution and the substrate, that comprises: placing a conductive substrate in contact with a conductive solution which initially comprises a solvent and one or more materials to be deposited upon the substrate, establishing and maintaining the solution and the substrate at a temperature at which the solution is liquid and is at or near saturation, passing an electric current across the solution-substrate system in such a way that cooling is effected at the interface between the liquid solution and the substrate, said cooling occurring only during the time in which electric current flows across the interface and only at the region of said interface, the rest of the solution-substrate system, except said interface, being maintained at the temperature that existed prior to the passage of the electric current, and controlling the magnitude of the electric current to control the current density at said interface.
Claim 5
Dependent Claim
53 words
A method as claimed in claim 1 in which the conductive solution comprises said solvent and a single, elemental or the constituents of a stoichiometric-compound material to be deposited and in which the density of the electric current at the interface is controlled to establish a desired rate of deposition of the material.
Claim 6
Dependent Claim
23 words
A method as claimed in claim 2 in which the current density at the interface is varied to change the rate of deposition.
Claim 7
Dependent Claim
28 words
A method as claimed in claim 3 in which the current density is varied at a uniform, unidirectional rate to establish a desired change in the deposition rate.
Claim 8
Dependent Claim
25 words
A method as claimed in claim 3 in which the current density is varied abruptly at a predetermined time during growth to form a junction.
Claim 9
Dependent Claim
48 words
A method as claimed in claim 1 in which the conductive solution contains a plurality of materials to be co-deposited and in which the density of the electric current at the interface is controlled to establish a desired deposition rate for each material of the plurality of materials.
Claim 10
Dependent Claim
31 words
A method as claimed in claim 6 in which the current density at the interface is varied at a predetermined uniform, unidirectional rate to establish a uniform change in the deposition.
Claim 11
Dependent Claim
29 words
A method as claimed in claim 6 in which the current density at the interface is varied abruptly at a predetermined time during growth to form a semiconductor junction.
Claim 12
Dependent Claim
56 words
A method as claimed in claim 1 in which one of said materials in the solution is a matrix material and another of said materials is a dopant, the matrix material and the dopant being co-deposited on the substrate and the rate of co-deposition of each being controlled by controlling the current density at the interface.
Claim 13
Dependent Claim
35 words
A method as claimed in claim 9 in which the current density at the interface is varied at a predetermined uniform undirectional rate to establish a uniform change in the composition of the deposited material.
Claim 14
Dependent Claim
29 words
A method as claimed in claim 9 in which the current density at the interface is varied abruptly at a predetermined time during growth to form a semiconductor junction.
Claim 15
Dependent Claim
39 words
A method as claimed in claim 9 in which said materials in the solution comprise a plurality of dopants and in which the current density at the interface is controlled to control the rate of deposition of each dopant.
Claim 16
Dependent Claim
35 words
A method as claimed in claim 12 in which the current density at the interface is varied at a predetermined uniform unidirectional rate to establish a uniform change in the composition of the deposited material.
Claim 17
Dependent Claim
29 words
A method as claimed in claim 12 in which the current density at the interface is varied abruptly at a predetermined time during growth to form a semiconductor junction.
Claim 18
Dependent Claim
60 words
A method as claimed in claim 1 in which the materials in the solution include a matrix material and a plurality of dopants, the concentration of the dopant impurities in the solution being chosen so that appropriate current density changes at any time during growth will be effective to cause one dopant to predominate in terms of rate of deposition.
Claim 19
Independent Claim
142 words
A method of growing a semiconductor epitaxial layer from a solution, that comprises: bringing a seed in contact with a conductive liquid solution which initially contains a solvent and a material to be deposited upon the seed to form the layer, establishing and maintaining the solution and the seed at a temperature at which the solution is at or near saturation, passing an electric current through the interface region between the solution and the seed in such a way that cooling is effected at the interface, said cooling occurring only during the passage of said electric current and only at the region of said interface, the rest of the solution-seed system, except said interface, being maintained at said temperature, and controlling the magnitude of the electric current to control the current density at said interface, thereby to control growth of the layer.
Claim 20
Independent Claim
142 words
A method of growing a semiconductor epitaxial layer from a solution, that comprises: bringing a seed in contact with a conductive liquid solution which initially contains a solvent and a material to be deposited upon the seed to form the layer, establishing and maintaining the solution and the seed at a temperature at which the solution is at or near saturation, passing an electric current through the interface region between the solution and the seed in such a way that cooling is effected at the interface, said cooling occurring only during the passage of said electric current and only at the region of said interface, the rest of the solution-seed system, except said interface, being maintained at said temperature, and controlling the magnitude of the electric current to control the current density at said interface, thereby to control growth of the layer.
Claim 21
Dependent Claim
50 words
A method as claimed in claim 16 in which the conductive solution contains said solvent and a single, elemental or stoichiometric compound material to be deposited and in which the density of the electric current at the interface is controlled to establish a desired rate of deposition of the material.
Claim 22
Dependent Claim
21 words
A method as claimed in claim 16 in which the conductive solution contains a matrix material and at least one dopant.
Claim 23
Independent Claim
150 words
A method of growing an epitaxial layer from a solution that initially contains a solvent and one or more materials to be deposited to form said layer, that comprises: establishing and maintaining the solution at a temperature at which it is liquid in form, said temperature being substantially the saturation temperature for the particular composition of the liquid, reducing the temperature of a region of the liquid to a level at which solidification occurs, passing an electric current through the interface area between the solution and the solid thus formed in a direction to effect cooling at the interface area, said cooling occurring only during passage of said electric current and only at the area of said interface, the rest of the growth system, except said interface, being maintained substantially at said saturation temperature, and controlling the magnitude of the electric current to control the current density at said interface.
Claim 24
Independent Claim
150 words
A method of growing an epitaxial layer from a solution that initially contains a solvent and one or more materials to be deposited to form said layer, that comprises: establishing and maintaining the solution at a temperature at which it is liquid in form, said temperature being substantially the saturation temperature for the particular composition of the liquid, reducing the temperature of a region of the liquid to a level at which solidification occurs, passing an electric current through the interface area between the solution and the solid thus formed in a direction to effect cooling at the interface area, said cooling occurring only during passage of said electric current and only at the area of said interface, the rest of the growth system, except said interface, being maintained substantially at said saturation temperature, and controlling the magnitude of the electric current to control the current density at said interface.
Claim 25
Dependent Claim
19 words
A method as claimed in claim 19 in which said composition comprises materials which form a semiconductor upon solidification.
Claim 26
Dependent Claim
35 words
A method as claimed in claim 20 in which the Electric current is d-c and in which at a predetermined time the level of current is changed abruptly to effect formation of a semiconductor junction.
Claim 27
Dependent Claim
18 words
A method as claimed in claim 21 in which said materials are indium, antimony and the dopant tellurium.
Claim 28
Dependent Claim
30 words
A method as claimed in claim 21 in which said materials comprise group III-V systems which form a matrix material and at least one group IV element as a dopant.
Claim 29
Dependent Claim
64 words
A method as claimed in claim 23 in which the matrix material and dopant are adapted to form either a p-type semiconductor or an n-type semiconductor, depending upon the concentration of dopant in the solid, and in which the ratios of material constituents in the solution are chosen and current densities are regulated to grow the semiconductor in the form of a p-n junction.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-21 | 1978-10-21 | 1979-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-21 | 1982-10-21 | 1983-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-21 | 1986-10-21 | 1987-04-22 | $7700.00 | Window Closed / Lapsed |