DE1901752A1 - Method for producing a single crystal in a non-monocrystalline substrate - Google Patents

Description

January 14, 1969 Docket FI 96? 084 Serial No. 697 770 Dr.Schie / E

Applicant: International Business Machines Corporation, Armonk, N.Y. 10 504 (V.St.A.)

Representative: Patent attorney Dr.-Ing. Rudolf Schiering, 7030 Böblingen / Württ., Westerwaldweg 4

Process for the production of a single-crystal stall in one non-monocrystalline substrate

The invention relates to a method for producing a single crystal in a non-monocrystalline substrate. at The fabrication of integrated circuits with silicon requires that the substrate be made of a single crystal to form the matrix for the integrated circuits. To have a single crystal substrate, it is necessary. to grow a single crystal plate, and then by special means to divide the wafer into a number of single crystal substrates. This well-known Method is a relatively expensive process. However, it provides a single crystal substrate.

Since only a small part of the total area of the substrate is used for the integrated circuits, the Growing a single crystal substrate to consume much more silicon than it actually does to form it of the integrated circuits required.

Furthermore, after the formation of the various integrated circuits in the substrate, it is necessary that the To electrically isolate circuits from one another by suitable means. Such means are e.g. B. PN junctions or a dielectric material

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The invention solves the problems discussed above by a method for selective growth in a more discreet manner Single crystals of silicon in a non-monocrystalline substrate made of dielectric material. The procedure after The invention switches not only the need for growing a single crystal substrate but also the use electrically isolated integrated circuits from each other, since the diskx ^ eten single crystals of silicon are already separated from each other due to the substrate material. This substrate material can either be polycrystalline or be amorphous.

The method according to the invention thus leads to a reduction in the cost of forming integrated circuits by eliminating the need for a single crystal substrate in which the integrated circuits are to be formed. D ^ the integrated circuits actually Framing only a small part of the total volume of the substrate is also achieved by the method according to the invention a substantial reduction in the amount of silicon required.

Since the method according to the invention allows the crystal to be grown at temperatures which are substantially below the melting point of silicon, the risk of diffusion of impurities is considerably reduced. The lowering of the temperature is, for example, in the invention 55O ⁰ C to 4-5O ⁰ G below the melting point of the silicon. Thus, the invention provides better control of the contaminant concentration in each of the crystals.

A layer of single crystal silicon has already been proposed to grow on a ceramic substrate on which there is a layer of glass. This layer breeding but does not provide electrical insulation of the input

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crystal from silicon against another single crystal Silicon · This proposed method is therefore not very useful for integrated circuits if one considers the Want to save extra costs of electrical insulation for the various circuits after their formation.

It has also been proposed to grow single crystals of silicon on a substrate made of amorphous Consists of quartz and is coated with a thin layer of gold. This type of breeding was not produced, it has arise purely by chance. The invention overcomes this problem by specifically selecting where each the silicon monocrystals are to be grown. In addition, it is ensured in the method according to the invention, that nucleation only takes place on one point of a gold sphere, with only a single crystal of silicon is produced by every gold ball. The proposed method is not able to guarantee that only a single crystal is created.

It has also been proposed to collect single crystals of silicon from a substrate of single crystal silicon using a gold ball to grow. This method does not provide any electrically isolated single crystals and enables nor does it control the growth of the crystal in a particular direction with only one single crystal on each Gold ball, as is done in the invention. In addition, the method already proposed requires that the Substrate is a silicon single crystal.

The aim of the invention is to provide a method for growing single crystals in a polycrystalline or amorphous substrate.

Another object of the invention is to provide one

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Method for controlling the nucleation of a material in a body made of a different material

Another object of the invention is to provide a method for the selective growth of discrete single crystals in openings or holes, which in a polycrystalline or amorphous substrate are included.

Yet another object of the invention is to provide a number of single crystal members in a non-monocrystalline Substrate.

Another object of the invention is to provide one dielectric substrate made of non-monocrystalline material with a number of single crystal parts in which monolithic, integrated circuits can be formed »

For a method for producing a single crystal in a non-monocrystalline substrate, the invention consists in that a body made of a first material is placed in a geometric recess in the substrate, that the body is heated in an inert atmosphere until it melts, that with the Body comes into contact with an atmosphere which contains a second material, wherein the body is further heated and is brought to a temperature which is greater than the eutectic temperature of the two materials, until the second material is absorbed in the body that a sufficient temperature gradient is maintained on the body to on the body with the higher temperature of the gradient Keiabildung as "generate only a single site, wherein the. upper part of the body has the atmosphere with the second material contact, that in continuation of the process the atmosphere with the second material is kept in contact with the body,

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while the body is at a temperature that above the eutectic temperature of the two materials until the desired height of the single crystal is reached is"

The invention will be explained in more detail below with reference to the schematic drawings for an exemplary embodiment explained.

Fig. 1 is a schematic representation of an apparatus for carrying out the method according to the invention.

Ifig. Figure 2 is a phase diagram of the gold-silicon system.

Fig. 5 is an enlarged sectional drawing of a part of a non-monocrystalline substrate with gold balls inlaid in recesses.

FIG. 4 is an enlarged sectional view of a portion of the non- _{monocrystalline substrate of FIG. 9} with single crystal portions grown.

5 is a perspective illustration _9, partially in section, of the non-monocrystalline substrate according to FIGS. 3 and 4 with silicon crystal parts, the upper surface parts of which have the same plane as the upper surface of the non-monocrystalline substrate.

Fig. 6 is a phase diagram of the gold-germanium system. Figure 7 is a phase diagram of the arsenic-gallium system. Fig. 8 is a phase diagram of the arsenic-indium systemesis

The apparatus shown in Fig. 1 for carrying out the process

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driving according to the invention contains a reactor tube 10, which is preferably made of quartz and functions like an oven to create a controlled atmosphere. In the Inside the tube 10, a selected atmosphere is introduced through the inlet pipe 11 and through the outlet pipe 12 discharged. The outlet pipe 12 "is located on the end part 14 · which seals the open end of the drill 10 ·

_{Inside the tube 10 is embedded 9} in a non-monocrystalline substrate 15 which is located on a holder 16. The holder 16 is connected to an outwardly directed handle 17. Haa & Griff 1? is through the rear member 14 passes felt _s so that one may adjust the position of the substrate 15 within the Söhre 10th

The holder IS and the handle 1? "consist of a te rial 5 which chemically with all elements within the EöliX-s 10 and with the flowing gas and vapors un- ■: j1 ^.", sm is ο The holder 16 and the handle 17 can, for. Bo from QuarSc, Alumiaiix® or a suitably layered Gr-apfe.it "order» The -worn holder 16 trageae Siibstratkör-P @ r 15 x-iiht irorteilhaft on sines, Klotz IS ₉ which has the effect © ines Hitseafelasses ~ has ο The Block 18 is made of a material which has not chemically reacted with the vapors flowing through tube 10. Block 18 could be made of silicon or a suitably coated graphite, for example

The substrate 15 can be made from any polycrystalline material or from an amorphous substance. The amorphous substance is, for example, quartz. The polycrystalline substance could "for example, a lamellier» tes kei ^ Amish material, for _{a. Β} Θ © ia metallic oxide ssiru Such metallic Oseyde are g _o B ₀ AluminiiimosEyd, and

Furthermore, the substrate can be

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mixed oxide ceramics, ζ. B. a mixture of oxides of Be aluminum, silicon and magnesium.

According to FIG. 3, the substrate 15 contains a number of depressions 19 'which are formed in a surface of 15 are and which are used to hold metallic, spherical bodies or balls 20 · They consist of a binary Alloy with the element introduced into the interior of the tube 10 through the inlet pipe 11 as vapor. The two Elements should be able to form liquid solutions. These liquid solutions have components from which a solid phase of the element, which is introduced into the tube 10 as vapor, is precipitated · If the steam contains silicon, the spherical body can for example be made of gold, tin, zinc or indium.

The reactor tube 10 contains a heating element 21 on its upper surface and a heating element on its lower surface 22. The heating elements 21 and 22 are preferably separate from one another. Each of the named heating elements is precisely controllable. By shaping the electrical heating elements 21 and 22 separation, regulation and the like. For each of these elements can be made independent.

A separate heating element 23 is also arranged above the heating element 21. The heating element 23 can be an infrared radiator or another radiant heater. The heating elements 23 can also be used as electrical wires around a semi-cylindrical tube wound.

The flow of gas and steam through the inlet pipe 11 into the interior of the tube 10 takes place via an intake manifold 24. This intake manifold is with a source 25 of hydrogen gas via the valve

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26 connected «With the valve 26 is the hydrogen flow adjustable from the source 25 to the manifold 24.

The intake manifold 24 · is also with a source tied together. This supplies a vapor of the material from which the single crystals are to be made. The source 27 can e.g. B. contain a silane, including, for example, tetrachlorosilane (SiOl ^) belongs. The flow of gas or vapor from source 27 into manifold 24 is through the valve 28 adjustable.

The hydrogen serves both as a carrier for the tetrachlorosilane as well as reactants therefor.

The suction manifold 24 is also with a source an inert gas, ζ. B. helium connected. The river of the Inert gas from the source 29 into the manifold 24 can be regulated by a valve 30. The inert gas works like a cleaning agent for the inside of the reactor tube 10

In one embodiment of the method according to the invention, the substrate 15 is made of various laminates ceramic materials, e.g. B. from mixed metal oxides of aluminum, silicon, zirconium, calcium, magnesium, Strontium, barium, titanium and iron. The substrates can also be made of quartz.

The recesses 19 in the substrate 15 have a cylindrical shape with a diameter of twelve thousandths and a depth from five to ten thousandth units of length. The spherical bodies 20 are made of gold and in the exemplary embodiment were ten thousandths in diameter. The spherical bodies 20 are at their upper .Oberfläche essentially? borrowed parallel to the surface of the substrate 15 in which the recesses '19 are formed. you can

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to the outside beyond the surface at a distance extend, which is not larger than the radius of the spherical body 20. This ensures an interaction between the wall of the recess 19 and the spherical body 20 so that any steam flow therebetween to the bottom of the recess 19 is limited. It should be noted, however, that it is not for the spherical body 20 is required to expand into the recess 19 with a specific distance.

The log passed in an experimental version by the inventor 18 made of silicon, while the holder 16 and its handle were made of quartz. The diameter inside the Reactor tube was about 25 mm. After the introduction of the Substrates 15 into the reactor tube 10 and after closing of the open end 14 of the tube 10 through which the substrate 15 was introduced, the valve 30 was opened so that the inert gas helium from the source 29 into the interior of the Tube 10 flowed in via inlet tube 11. The introduced gas was allowed to flow out through the exhaust pipe 12 and clean the system during passage.

After the cleaning process with the helium, the valve 30 was closed and the valve 26 opened, so that the helium flow was stopped and water flow from the source 25 with could flow out at a predetermined speed.

The heating elements 21 to 23 were then put into operation in order to create a temperature gradient on the spherical body 20 to manufacture. This gradient runs essentially perpendicular to the surface of the substrate 15. The temperature at the bottom of spherical body 20 was about 1063 C. This is the melting point of gold. Accordingly, the spherical bodies made of gold are melted.

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The valve 28 was then opened so that tetrachlorosilane could flow into the branch pipe 24 with the hydrogen from the source 25. The valves 26 and 28 have been adjusted ₉ so that the molar ratio of tetrachlorosilane to hydrogen is 0.001. The flow of this atmosphere with the molar ratio of 0.001 took thirty minutes.

Thereafter, the temperature at the bottom of the spherical body 20 was reduced to 950 ° 0 and the molar ratio through corresponding regulation of the valves 26 and 28 increased to 0.02. This response was about an "to a and a half" Hour continued. During this time, a silicon single crystal became from the lower part of each of the gold bodies 20 bred through the body 20 and out to the upper part

After this period of time, valve 28 was closed to stop the flow of the tetrachlorosilane. The river however, the hydrogen was continued for a sufficient period of time to purge the system. Then was- * the electrical heating elements 21 to 2 $ switched off and the substrate 15 removed from the reactor tube 10.

According to FIG. 2, the reaction is continued at the temperature of 1063 ° C. until the amount of silicon in the gold body is in Excess of the gold liquid line at the temperature "is at which nucleation for the formation of the single crystal occurs. According to Fig. 2, the process is continued at the higher temperature until, for example, a point 31 is reached.

The point 31 indicates an alloy that has a larger one Silicon percentage than in item 32. In item 32, the composition of the silicon is at a temperature of 950 ° C. This corresponds to the requirement that the Silicon percentage in excess of the gold liquidus line is at the temperature at which the crystal grows

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takes place. When the temperature is at the bottom of the spherical Body 20 has decreased to 950 ° 0, the silicon percentage increases in the gold body 20 up to the point 33 to · At this point the temperature of 950 ° 0 at the bottom of the spherical body 20 is reached.

When the silicon concentration in body 20 reaches point 34-, the body 20 is saturated with silicon. A continuation of the introduction of silicon into the body 20 from the vapor phase leads to an oversaturation of the body 20 with silicon, so that a necessary condition for the nucleation of solid silicon is created. A preferred one heterogeneous nucleation site is created by the interfacial contact between the bottom of the body 20 and the Substrate 15 created. At this point the supersaturation is required for solid silicon nucleation is significantly lower than that required for solid formation Silicon nuclei required by homogeneous nucleation in the body

A further increase causes nucleation only at the bottom of the spherical body 20 in the case of the imposed temperature gradient. This temperature gradient is given, for example, when there is a temperature on the upper part of the body 20 of 970 ° 0 and at the bottom of the body 20 a temperature of 950 ° C is maintained. The higher temperature at the top j Part of the body 20 brings a higher saturated silicon concentration in the liquid solution. So if the solution is supersaturated with silicon, the degree of supersaturation is less at the top of the body 20 than at the bottom of the body 20. This creates a greater driving force for nucleation on the lower part of the body 20. the Combined directional control of temperature and body-substrate contact ensures that nucleation occurs only at one point on the body 20.

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Once nucleation of the solid silicon crystal takes place, is the growth of the crystal through the flow of the Silicon from the vapor phase is controlled by the liquid solution with the help of the temperature gradient.

It should be noted that it is not necessary to carry out the process according to the invention through an initial temperature at the lower Part of the body start 20 "at the melting temperature of gold. Instead, a slightly lower temperature could be used are used, the gold body 20 would melt if the gold liquidus straight with the addition of silicon Has passage to the body 20 · It would be necessary to be sure fc to indicate that the operation would continue at the higher of the selected temperatures until the composition of the body 20 has a percentage of silicon which is greater than the composition of the silicon the gold-liquidus line at the lower temperature at which nucleation occurs naturally it is necessary that the lowest temperature of the body 20 is greater than the eutectic temperature (about J00 ° C) of the composition

In addition to the nucleation influencing on the lower part of the body 20 the temperature gradient is the interfacial tension at the point where the body 20 rests on the W lower wall of the recess 19 lower than 20, at the upper part of the body, this has the result that the lower interfacial tension is also a factor in ensuring that nucleation at the lower part of the body 20 occurs.

In addition, because of the high contact angle between the body 20 and the bottom of the recess 19, the heterogeneous Localized nucleation and thus the 'number of nuclei that want to form on the substrate 15 is reduced. The through

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ensures high contact angles created by the body 20, that heterogeneous nucleation takes place on the lower part of the body 20.

If the applied temperature gradient is substantially perpendicular to the surface of the substrate 15, then the silicon crystals grow substantially perpendicular to the surface of the substrate 15, i. H. they grow in the direction of the temperature gradient. If the temperature gradient on the gold body 20 run at an angle should, then the crystal also grows with this angle.

The final crystal of silicon is about 0.0001 percent gold in the examples given above. This amount of gold can be desirable to z. B. to limit the carrier life. Should it be desired to remove this gold, then one would have to use another suitable method, e.g. B. apply the blotter technique.

In theory, the temperature at the lower part of the gold body 20 could be any temperature above the eutectic one Temperature of the gold-silicon alloy and below the Be the melting point of silicon to produce the silicon single crystal. In practice, however, there are working temperatures between 600 ° C and 1200 ° 0. Furthermore, the temperature gradient be greater than 50 ° C per centimeter of vertical displacement in this reactor tube on the gold body 20. at This temperature gradient is the flow rate of hydrogen through the reactor tube 10 before Substrate 15 about one liter per minute.

In Fig. 4-, the substrate 15 is with separated silicon single crystal elements or parts 35 shown. These parts 35 have grown from the gold bodies 20. You own

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in the upper area parts 36, which are made of a silicon-gold alloy exist. The growth of the single crystal parts 35 therefore stops when the upper parts of the crystal parts over the top of the substrate 15. At this point it is necessary to remove the part 36 of each of the Single crystal parts 35 with the silicon-gold alloy remove. The silicon-gold alloy can be removed mechanically or with the aid of chemicals Means done. In the case of mechanical means, the abrasion method could be used. When used chemical means one could use mercury, aem the gold is dissolved with the gold to form an amalgam. When the upper surface is required to be aer Single crystal parts 35 in the same plane with the upper surface of the substrate, as shown in Mg. 5, then it would be necessary to place all of the silicon over the top Surface of the substrate 15 to remove. You could do this e.g. B. can be achieved by polishing. It is of course not necessary that the upper surface of the single crystal parts 35 is flush with the upper surface of the substrate 15 lies if one wanted to form integrated circuits there.

The substrate body 15 shown in FIG. 5 contains single crystal parts 35 'whose protruding parts have been removed. the In the embodiment according to FIG. 5, single crystals 35 are only silicon single crystals with a small amount of gold manufactured. With the top surface of each of the elements 35 flush with the top surface of the substrate 15, the various members 35 are electrically isolated from one another in the substrate 15 and form separate islands. Accordingly, the method of the invention provides a product in which monolithic integrated circuits in each of the single crystal members 35 'which are isolated from one another in the substrate 15 can be formed. That is,

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each of the single crystal members 55 is capable of being monolithic to include integrated circuit.

While gold was used in the suggested examples, any other metal with a lower melting temperature can be used can be used as the material from which the crystal is grown. However, it is desirable to have gold in the silicon crystal because of the reduction in the charge carrier lifetime

While in the example used the block 18 is made of silicon and is effective as a heat extraction, it would it may also be possible that the silicon crystals can grow in the substrate 15 without the heat extraction member. However is a larger amount of heat supplied from the heating element 23 is required to achieve the desired temperature gradient to reach on the body 20.

Since the gold in the body 20 has a lower interfacial tension with the passing silicon than the substrate 15, the regulation of the molar ratio of tetrachlorosilane to hydrogen is ensured, so that no silicon on the substrate 15 is formed from the tetrachlorosilane. The silicon is therefore only formed on the body 20

It is accordingly important that the material of the body 20 have a lower interfacial tension with the material, from which the crystal is to be grown, as the material of the substrate, 15 · On the other hand, the material could grow on the substrate 15 as well as on the body 20.

So far it has been described that the recess 19 is a cylindrical Should have shape. However, the invention is not limited to this; rather, the depression can also be different

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Have shapes and ζ. B. be conical or the shape of a conical stump. With a conical shape of the recess 19, there would be a greater possibility of formation of polycrystals in the body 20, so that a more precise control of the parameters is required · The The conical shape of the recess is therefore not as desirable as the cylindrical recess.

Forming the recess in the shape of a truncated cone would of course be very desirable, despite the cost such a shape for 19 are much larger than in the case of a cylindrical recess. Has the depression 19 the shape of a truncated cone, then nucleation occurs on the lower part of the body 20 and a denser one Seat between the body 20 and the wall of the recess

19 could be formed to ensure that all of the silicon from the tetraehlorosilane has to go into the body

20 in the upper part of the body 20

While the gas from which the crystals get their material for crystal formation consists of tetrachlorosilane, As indicated in the previous example, it is of course possible to use any other silane. A such silane could e.g. B. monosilane (SiH ^), where then the hydrogen from source 25 would not be necessary. Instead of helium gas from the source 29, one could use monosilane as the carrier gas. The hydrogen won't used to react with the monosilane.

Furthermore, other types of material could also be used, to grow crystals on the substrate 15 · So could z. B. Germanium can be used to form crystals on the substrate 15 with the bodies 20 that are still with gold are to breed. The gas from which the germanium could be extracted would be a german. Such a German

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- 17 could ζ. B. be tetrachlorogerman (GeCIU)

The phase diagram of gold and germanium is in FIG. 6 · Points 37 to 40 in FIG. 6 correspond the points 31 "to 34 in the phase diagram according to FIG. 2 for Gold and silicon. The same reactions take place as described for "gold and silicon".

The result is single crystals of germanium · Let b «

lies,

it should be noted that the eutectic temperature is 356 ° C

As already mentioned, the bodies 20 can also consist of a material other than gold. For example, the body can Contain gallium · The gas from which this metal ν is obtained would be, for example, arsine (AsH,). With this formation of crystals the Single crystals are a compound of gallium arsenide with arsenic, which on the body 20 from the arsine is knocked down. The gallium arsenide is the mixture of equilibria resulting from the arsenic-rich side of the gallium-rich Eutectic is formed.

According to Fig. 7, the gallium-rich eutectic temperature is 29.5 ° 0. B. the temperature of the body 20 is kept at 800 ^° C., then a nucleation occurs in the body 20 · Since this temperature is above the melting point of the gallium, the gallium bodies can be heated up to this temperature with the arsine that is introduced directly at the same time . Accordingly, it is not necessary to bring the bodies 20 to a first temperature and then to bring the temperature of the bodies to a second temperature which is lower than when silicon or germanium is deposited on gold.

Accordingly, along the straight line of gallium liquidus, there is

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Saturation takes place as along the arsenic liquidus line. This means that single crystals with the composition of Gallium arsenide can be formed on the arsenic-rich side of the gallium-rich eutectic · The phase diagram of arsenic and gallium is such that it is not feasible to produce only arsenic as a material for the single crystals.

It will be understood that the body 20 could be formed from one member selected from the group consisting of Boron, gallium, and indium with the material which contains deposited in liquid solution of the body 20 from the vapor selected from the group consisting of phosphorus, arsenic and antimony will. The vapor from which the material is obtained is a hydride or a halide with phosphorus, arsenic or antimony. The hydride could e.g. B. Arsenic hydride (AsH,) or phosphorus hydride (PH,). The halide could e.g. Arsenic trichloride (AsCl,), arsenic tripromide (AsBr,), arsenic trigulfide (AsI,), phosphorus trichloride (PCI,), phosphorus tribromide (PBr,), phosphorus triiodide (PJ,) or antimony trichloride (SbCl,).

When the single crystals on the substrate 15 from one of the above are grown, the monocrystalline material is a compound of the materials of the body 20 and the metal which is deposited into the liquid ™ solution of the body 20. So could the compound of the monocrystalline material gallium phosphide ((GaP), gallium arsenide (GaAs), gallium antimonide (GaSb), indium arsenide (InAs) or indium antimonide (InSb) ζ. Β. be.

The phase diagram for two of these materials, arsenic and indium, is shown in FIG. The eutectic temperature for this alloy is 155 j2 ° C.

As already described in connection with the gallium arsenide

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ben, single crystals could be formed from indium arsenide, which is the equilibrium solid alloy found on the arsenic-rich side of the indium-rich eutectic is formed. Like again in connection with the gallium arsenide As discussed, it is only necessary to have a temperature slightly above the melting temperature of the indium in the selection. If z. B. a temperature of 800 ° C has been selected, it is not necessary to vary this temperature, as this is the case with gold-silicon and gold-germanium materials was the case. Choosing a temperature, such as B. 800 ° C wants to ensure the formation of single crystals without any further change in temperature as the vapor containing arsenic passes over substrate 15.

It has already been described that the substrate 15 consists of may be made of a dielectric material. It. however, it is clear that this material is also a conductive Material, if this were required for growing the crystals

While a temperature gradient is established on the body 20 to melt it, it is clear that the temperature gradient on the body 20 is not required if the melt is provided so that the temperature at the bottom Part of the body 20 is not lower than the melting point of the material of the body 20. The temperature gradient however, must be applied during this initiation stage when the temperature at the lower part of the body 20 is below the melting point of the material of the body 20.

Some examples of the method according to the invention are given below. It should be mentioned that the invention should not be limited to these exemplary embodiments.

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Example I.

A quartz reactor tube with a diameter of 25 millimeters was placed in a gripping oven. This furnace was wired to allow independent control in its upper and lower turns. An auxiliary heater was coiled in a 72 mm long semi-cylindrical tube. This Auxiliary heater was located on the reactor tube directly above the location of the introduced substrate. The stove could can be brought to 800 ° C · By the auxiliary heating higher temperatures can be regulated in the oven.

P The reactor tube had a simple gas-mixing manifold for introducing the desired atmosphere into the reactor tube · This manifold was in a line for the introduction of the pure hydrogen or helium and in a second line for the introduction of the controlled Partial pressure of tetrachlorosilane with the tetra chlorosilane set up in a saturation at around 24 ° C.

A stream of hydrogen was passed through the reactor tube prior to deposition on any substrate in the reactor tube directed at a rate of one liter per minute. Deposits platinum and 10% rhodium in the reactor tube a one-centimeter ™ layer vertical to the tube. Furthermore, it was made in an atmosphere Hydrogen measured the temperature difference, after which a temperature gradient of 8 ° C is established when the temperature was set to a value of 950 ° C. The substrate consisted of a laminated polycrystalline material, deposited on a thick block of silicon. The substrate was very close to the top surface the reactor tube and close to the auxiliary heater. The temperature gradient was controlled with the help of two thermocouples. The substrate was placed on a thick chunk of silicon which acted as a heat drain.

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The substrate, which is made of a mixed ceramic

ρ oxide consisted of a size of about 1 cm and of about 1 mm thick. The substrate was specially designed with four cylindrical holes. The diameter of the Hole was 0.012 inches. The depth of the hole was 0.005 "to 0.010". These holes were near the center of the substrate.

The gold bodies, which were 0.010 inches in diameter, were placed in each of the holes. The body consisted of 99 »99% pure gold.

The substrate with the four gold balls was then placed in a hydrogen flow rate of one liter per minute heated · Both heaters were used for heating for one hour at a temperature of 950 C. The thermocouples were under the resin holder of the Substrates. This position of the thermocouple is in essentially the same as the position of the lower thermocouple when the temperature gradient of 8 ° C is measured became.

The concentration of the tetrachlorosilane was then introduced into the reactor tube and held at 0.05 for thirty minutes Mole percent held. The concentration of the tetrachlorosilane was then increased to 2 mole percent for two hours. The reference temperature of 950 ° C was maintained over the duration of the entire process held.

The resulting material in this example was highly polycrystalline Silicon.

Example II

All of the conditions and parameters from Example I were also used here, with the exception that the

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draw temperature was set to 1050 ° C and the temperature gradient to 16 ° C. The temperature at the lower thermocouple was 1050 ° C. As in the case of Example I, the material produced in all holes was also highly polycrystalline Silicon.

Example III

All conditions and parameters of Example I were 'mrh Used here, but with the exception that the temperature gradient was about 100 ° C. Throw in three out of four holes grown the silicon single crystals. A three-grain silicon crystal had grown in the fourth hole.

Example IV

All conditions and parameters from Example I have been adopted here, with the exception that the reference temperature was 1050 ° and the temperature gradient was about 100 °. The temperature at the lower thermocouple was 1050 G. Silicon single crystals were grown in all four holes.

The advantage of the invention consists in particular in the elimination the use of an additional process step for electrical insulation of integrated switching ' actions against each other after the formation in the substrate “Another The advantage of the invention is that the diffusion of impurity atoms is reduced, since the process is lower Temperatures is operated than was previously needed for the epitaxial method. Another advantage of the invention is that it can be used for a single crystal substrate in which integrated circuits are formed can become unnecessary. Another advantage of the invention is given that the required Amount of silicon is significantly reduced.

Claims °

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Claims (1)

Claims Method for producing a single crystal in a non-monocrystalline substrate, characterized in that that a body made of a first material is brought into a geometric recess in the substrate, that the body is heated until it melts in an inert atmosphere that contacts an atmosphere with the body which contains a second material, wherein the body continues to be heated and to a temperature is brought, which is greater than the eutectic temperature of the two materials, namely until the second material is absorbed in the body that a sufficient temperature gradient is maintained on the body, in order to generate nucleation in only one single point on the body with the higher temperature of the gradient, at the upper part of the body the atmosphere is in contact with the second material, that in continuation of the process the atmosphere with the second material is kept in contact with the body while the body is at a temperature above the eutectic temperature of the two materials until the desired height of the single crystal is reached. 2.) The method according to claim 1, characterized in that the melted body for a predetermined Period of time is kept at a predetermined temperature that the second material containing Atmosphere is brought into contact with the body, which is heated to a first predetermined temperature until the percentage of the second material in the body is the liquid line of the second material at a second predetermined temperature has exceeded that is greater than the eutectic temperature that the tem- - 24 - 909836 / U3Ö temperature of the body then to the second predetermined Temperature is decreased and maintained at the second predetermined temperature until the desired level of the Single crystal is achieved. 3 «) Method according to claim 2, characterized in that that the first material consists of gold, the second material consists of silicon and that the atmosphere with the silicon consists of a silane. 4.) The method according to claim 3 ^ characterized in that that the silane is a tetrachlorosilane. 5.) The method according to claim 1 to 3 »characterized in that the body is spherical and the recess is cylindrical, that the cylinder diameter is slightly larger than the ball diameter and that the recess is approximately is equal to the ball diameter. 6.) Process according to claims 1 to 5t, characterized in that that the substrate consists of a dielectric material. 7.) Process according to claims 1 to 6, characterized in that that a number ^ of depressions in the substrate is formed and that each of these depressions a body is inserted to make one out of each of these depressions To grow crystal. 8.) Process according to claims 1 to 7 »characterized in that that the temperature gradient across the body is substantially perpendicular to the surface of the wells containing substrate runs. - 25 - 909836/1436 9.) Process according to claims 1 to 8, characterized in that that the temperature gradient is established on the body when the body reaches the first predetermined Temperature is heated. 10.) Process according to claims 1 to 9 »characterized in that that the substrate is arranged on a heat dissipating material. 11.) Process according to claims 1 and 2 and 4 to 9, characterized in that the first material consists of gold, the second material consists of germanium and that the the atmosphere containing germanium is German. 12.) Process according to claims 1 and 2 and 4 to 9 » characterized in that the first material consists of gallium, the second material consists of arsenic and that the the atmosphere containing arsenic is arsine. 13.) Process according to claims 1 and 2 and 4 to 9 _t, characterized in that the first material is an element from the group with boron, gallium and indium, that the second material is an element which is selected from the group with phosphorus, Arsenic and antimony is selected and that the atmosphere containing the second material is a hydride or a halide. ) According to the method according to claims 1 to 13 produced monolithic integrated circuit, thereby characterized in that a substrate of non-monocrystalline material has a number of formed thereon Contains monocrystalline components that are separate from one another and each a monolithic integrated Has circuit. - 26 - 909836/14 jö 15.) Device according to. Claim 14, characterized in that that the monocrystalline components are arranged in separate depressions in the substrate. 16.) Device according to claims 14 .and 15 »thereby characterized in that the substrate is made of dielectric material. 17.) Device according to claims 14 to 16, characterized characterized in that the monocrystalline components consist of a material selected from a group is, which contains silicon and germanium 18.) Device according to claims 14 to I7, characterized characterized in that the monocrystalline components are formed from a compound, one of which is Materials is selected from a group consisting of boron, gallium and indium, and the other of its Materials is selected from a group which includes phosphorus, arsenic and antimony. 909836 / 143b " ω fc £ 9 _y Blank page