JPH0834697A - Pull-up growth method and device therefor - Google Patents

Abstract

PURPOSE:To obtain a means for growing a crystal with desired shape having a uniform composition from the shoulder in relation to the pull-up growth of a multielement semiconductor crystal by fixing the temp. of a growth interface. CONSTITUTION:A source 3 consisting of >=1 kind of raw material among the raw materials, e.g. GaAs, is replenished to the melt or soln. 2 of a multielement semiconductor consisting of >=2 kinds of raw materials, e.g. InGaAs, while controlling the feed rate with a function involving time, and a seed crystal 5 dipped in the melt or soln. 2 is pulled up to grow a crystal 7 consisting of InGaAs, for example, as a multielement semiconductor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulling growth method and a pulling growth apparatus suitable for growing a multi-element compound semiconductor crystal.

Generally, in manufacturing a compound semiconductor device, a binary compound semiconductor is used as a substrate, and a crystal layer of a compound semiconductor of binary or more is grown on the substrate.

However, there is a problem of lattice mismatch between the binary compound semiconductor substrate and the ternary compound semiconductor crystal layer due to the difference in lattice constant. That is, when a ternary compound semiconductor crystal layer is directly grown on a binary compound semiconductor substrate, defects due to lattice mismatch are introduced, so that the performance of a compound semiconductor device manufactured using it is extremely low. turn into.

In order to avoid the lattice mismatch between the binary compound semiconductor substrate and the ternary compound semiconductor crystal layer as described above, it is also possible to interpose a compositionally graded layer in which the lattice constant is gradually changed. However, it goes without saying that the process becomes complicated, and it is desirable to eliminate the composition gradient layer if possible. Therefore, it is desired to realize a compound semiconductor substrate of ternary or more with sufficient practicality. ing.

[0005]

2. Description of the Related Art FIG. 4 is a principal part explanatory view showing a pulling growth apparatus for explaining a conventional technique relating to pulling growth of a ternary compound semiconductor crystal.

In the figure, 1 is a crucible, 2 is a melt (or solution), 3 is a compound semiconductor source for replenishing the melt, and 4 is a rod for inserting / removing the source 3 into / from the melt 2. 5,
Is a seed crystal, 6 is a pulling shaft for immersing the seed crystal 5 in the melt 2 and then pulling it, 7 is a growing compound semiconductor crystal, 7
A is a shoulder of the crystal 7, and 8 is a load cell for measuring the weight of the crystal 7.

Usually, in the process of growing a compound semiconductor crystal of ternary or more from a melt (or solution) by a pulling method, it grows due to a difference in distribution coefficient (= segregation coefficient) of solute elements. The compound semiconductor crystal has a composition gradient in the growth direction.

Further, in the melt (or solution), a specific solute element will be depleted as the crystal grows, so supplementing the depleting element is a ternary or higher compound having a uniform composition. It is essential for manufacturing a semiconductor crystal substrate.

In the device seen in FIG. 4, for example In
_When growing _x Ga _1-x As, the melt 2 is a mixed melt of GaAs and InAs, and the seed crystal 5 is GaA.
The s crystal or InGaAs crystal is used, and the seed crystal 5 is immersed in the melt 2 maintained at _a constant temperature T _a and then pulled up. At the same time, the temperature of the growth interface is lowered from T _a to T _b to reduce the diameter of the crystal. The shoulder portion 7A is made larger.

Then, the growth interface is maintained at a constant temperature T _b , and the source 3 is pulled up and grown while being replenished into the melt 2 by the rod 4 at a constant rate to form a straight body portion of the crystal 7. It was

This straight body portion is grown with a constant composition by pulling and growing at a constant temperature T _b , which will be described with reference to the phase diagram of In _x Ga _1-x As. To do.

FIG. 5 shows In_xGa_1-xIt is a state diagram of As
The In composition (In_xGa _1-xAs)
The vertical axis indicates the growth temperature [° C].

The composition of the initial melt 2 is In _xL0 Ga _{1 -xL0}
As, In _xL0 Ga in the state diagram of FIG.
_The temperature at which the composition of _1-xL0 As and the liquidus line intersect is T _a . That is, T _a corresponds to the temperature at which the melt is first put in the crucible and begins to solidify.

If the crystal 7 is pulled up in the above state, segregation causes the In composition in the melt 2 to increase, and x _L >.
The composition is x _L0 . At this time, the growth interface temperature is also lowered from T _a depending on the composition.

In the ordinary supplementary growth, the shoulder portion 7A of the crystal 7 is grown by the slow cooling growth as described above, and thereafter, the depleted GaAs is supplemented while maintaining the constant temperature T _b. To grow an In _xs Ga _1-xs As mixed crystal having a constant composition. That is, the desired solid phase composition In _xs Ga _1-xs A
The temperature at which s and the solidus line intersect is T _b .

[0016]

Generally, when pull-up growth is performed, the volume of the shoulder 7A occupying the entire crystal 7 is small until the crystal 7 reaches a desired diameter. The required solidification rate of the melt 2 is small.

FIG. 6 is a diagram showing the relationship between the solidification rate of In _x Ga _1-x As and the composition x of the solid phase, where the horizontal axis represents the solidification rate and the vertical axis represents the solid phase composition x. It is taken.

Conventionally prepared, for example, In _0.05
In the case of Ga _0.95 As, since the composition gradient at a small solidification rate is small as shown in FIG. 6, after growing the shoulder portion 7A,
The source 3 made of GaAs is replenished to grow the straight body having a constant composition. In this case, supply G
The amount of aAs source W _GaAs is

[0019]

[Equation 2]

[0020] Where W _C is the growing InGa
The mass of As (mass increasing rate), the solid phase composition of the grown InGaAs is In _xs Ga _{1 -xs} As, and the liquid phase composition of the melt 2 is I.
n _xL Ga _{1 -xL} As, M _{GaAs and} M _InAs represent the molecular weights of GaAs and InAs, respectively.

By the way, In _x Ga having a large In composition
_{With 1-x} As (x> 0.10), GaAs in the melt 2 is rapidly depleted, so that a large composition gradient is already generated when the shoulder portion 7A is manufactured.

When a large composition change is caused, a large lattice strain is generated in the grown crystal, which makes it easy to polycrystallize during the growth, and the straight body portion thereafter becomes polycrystallized, Further, even after the growth, there is a problem that it becomes a factor that breaks the crystal when it is cut into a substrate.

It has been confirmed that the above-mentioned problems are not limited to the In system and are common to ternary compound semiconductor mixed crystals.

The present invention seeks to provide a means for growing a crystal of a desired shape having a constant composition from the shoulder while keeping the growth interface temperature constant.

[0025]

In the present invention, a melt (or a solution) of a multi-component semiconductor composed of two or more raw materials is replenished with one or more raw materials constituting the raw material, When a seed crystal immersed in a liquid (or a solution) is pulled up to grow the multi-component semiconductor, basically two means are provided, and the first means is to increase the replenishment rate of the raw material to be replenished. It is to control as a function of time, and the means will be described next.

Here, assuming that the multi-element semiconductor made of two or more raw materials is a multi-element semiconductor of element A, element B, and element C, the replenishing raw material is a semiconductor made of element B and element C. Preferably, the replenishment of the raw material is started at least at the same time as the start of the shoulder growth, or preferably at the same time as the seeding, and thereafter, the replenishment is controlled as usual. In particular, a crystal having a constant composition can be grown by keeping the growth interface temperature constant and growing the crystal.

When the liquid composed of the mixed crystal semiconductor of the element A, the element B and the element C is a melt, the descending speed is as shown in the equation of [Equation 1] and its symbolic description. ]
It is sufficient to pull up and grow so as to satisfy the formula. still,
If the raw material to be supplied is cylindrical or prismatic, it is convenient because the cross-sectional area S is constant.

The above formula of [Equation 1] is theoretically derived, and the basis thereof is Japanese Patent Application No. 4-21498 (Japanese Patent Application Laid-Open No. 5-221775) relating to the application of the present applicant. Is disclosed in.

During the crystal growth, the mass of the grown multi-element system semiconductor consisting of the element A, the element B and the element C is measured, and the descending speed of the raw material to be replenished is finely adjusted based on the measured mass, or the heating means is controlled to grow. It is advisable to keep the interface temperature constant.

Further, the element A is a Group 3 element other than the element B, the element B is a Group 3 element other than the element A, the element C is a Group 5 element, or the element C is a Group 3 element and the element A is an element. The Group 5 element other than B and the element B may be the Group 5 element other than the element A.

Furthermore, the elements A, B and C may be group IV elements.

Of the two means on which the present invention is based, the first means, that is, the means for controlling the replenishment rate of the material to be replenished as a function of time has been described above. Will be described.

The second means is to gradually increase the cross-sectional area S in which the source 3 made of a multi-element semiconductor of the replenishing elements B and C contacts the melt (or solution), and thereby the seed crystal 5 is obtained. To shoulder 7 to enlarge crystal 7 from the desired diameter
It is to grow A.

Specifically, the element B and the element C to be supplied are
The shape of the source 3 made of a multi-element semiconductor is a shape in which the tip is narrowed down, and in this case, depending on the shape, the source 3 is lowered at a constant speed for replenishment. Therefore, the shoulder portion 7A of the crystal 7 of good quality can be manufactured. Of course, the shape and the change in the descending speed may be combined.

Also in this case, the mass of the grown multi-element semiconductor composed of the element A, the element B and the element C is measured, and the descending speed of the source 3 is finely adjusted based on the measured mass, and the heating means is controlled. It is preferable to keep the growth interface temperature constant.

Further, the element A is a Group 3 element other than the element B, the element B is a Group 3 element other than the element A, the element C is a Group 5 element, or the element C is a Group 3 element and the element A is an element. The Group 5 element other than B and the element B may be the Group 5 element other than the element A.

Furthermore, the elements A, B and C may be group IV elements.

FIG. 1 is a principal part explanatory view showing a pulling growth apparatus for carrying out the pulling growth method of the present invention, and the same parts as those described with reference to FIG. 4 are designated by the same symbols. In the figure, 9 is a control device and 10 is a heater.

In the illustrated pulling growth apparatus, a crucible 1 is filled with a ternary melt (or solution) 2 composed of an element A, an element B and an element C, and a pulling shaft 6 is a seed crystal 5.
Is held and immersed in the melt 2 and then the crystal 7 is pulled up and grown. Further, the elements that are depleted in the melt 2 are replenished by immersing the source 3 attached to the rod 4.

The mass of the grown multi-element semiconductor crystal 7 composed of the element A, the element B and the element C is measured by the load cell 8, and the measured data is input to the controller 9 and the controller 9 Then, the crystal 7 is calculated so as to have a uniform composition, and the source descending speed and the heater 10 are controlled based on the values thus obtained.

Here, in the crystal 7 of the multi-element semiconductor composed of the element A, the element B, and the element C, the element A is an element of Group 3 or Group 5 and a plurality of elements is the element A. However, the melt 2 using the semiconductor made of the elements B and C as the source 3
The melting point of the semiconductor composed of the elements B and C is the same as the melting point of the semiconductor composed of the elements B and C because the crystal composed of the elements A, B and C is pulled up, that is, solidified at the same time as melting and replenishing Must be high compared to the melting point of the crystals consisting of. Therefore, for example, in the case of InGaAs, the element A is In and cannot be Ga.

Similarly, when the elements A, B, and C are all Group IV elements, the melting point of the source 3 which is a mixed crystal semiconductor including the elements B and C is the same as that of the elements A, B, and C. The melting point of the pulled crystal 7 must be higher than that of the pulled crystal 7. Specifically, the case where the crystal made of Si _x Ge _{1-x is} pulled with Ge as the element A and Si as the element B and C is given as an example. You can

From the above, in the pulling growth method and pulling growth apparatus according to the present invention,

(1) In a melt or solution (eg, melt or solution 2: FIG. 1) of a multi-component semiconductor (eg, InGaAs) composed of binary or more materials, a material (eg, melt) of one or more of the above materials (eg, The seed crystal (eg, seed crystal 5: FIG. 1) immersed in the melt or solution by controlling the supply rate of GaAs) as a function of time is pulled up to pull up the multi-element semiconductor (eg, InGaAs crystal 7: 1) is grown, or

(2) In the above (1), the multi-component semiconductor composed of two or more raw materials is a multi-component semiconductor composed of the element A (for example, In) and the element B (for example, Ga) and the element C (for example, As). (For example, InGaAs), and the raw material to be supplied to the melt or the solution (for example, the melt or the solution 2: FIG. 1) is a semiconductor composed of the elements B and C (for example, GaA).
s), or

(3) In the above (1) or (2), when the seed crystal (eg seed crystal 5: FIG. 1) is brought into contact with a melt or a solution (eg melt or solution 2: FIG. 1) To a melt or solution from a raw material (for example, source 3 made of GaAs:
1) characterized by starting the replenishment, or

(4) In the above (1), (2) or (3), the melt or solution (eg melt or solution 2: FIG. 1) is used as a raw material (eg GaAs source 3: FIG. 1). ) Is supplied to form a shoulder portion (for example, shoulder portion 7A: FIG. 1) that enlarges the crystal (for example, InGaAs crystal 7) from a seed crystal (for example, seed crystal 5: FIG. 1) to a desired diameter. Or

(5) In (1) or (2) or (3) or (4) above, a crystal (for example, a crystal 7 made of InGaAs) is produced while maintaining a constant growth interface temperature. Or

(6) In the above (1) or (2) or (3) or (4) or (5), the element A (for example In) and the element B (for example Ga) and the element C (for example As) are used. A compound semiconductor composed of a multi-element semiconductor (eg, InGaAs) is a melt (eg, melt 2), and a compound semiconductor composed of elements B and C, which are raw materials to be replenished (eg, GaA).
The descending speed of s) is

[Formula 1] where X _L : mixed crystal ratio of element A in the melt X _S : mixed crystal ratio of element A in the grown ternary mixed crystal semiconductor M _AC : element A and element C Molecular weight of compound semiconductor M _BC : molecular weight of compound semiconductor of element B and element C ρ _BC : density of compound semiconductor of element B and element C ρ _C : mixed crystal of grown element A, element B and element C Density of semiconductor S: Area where compound semiconductor consisting of element B and element C to be replenished contacts the melt surface r: Radius of mixed crystal semiconductor of grown element A and element B and element V: Grown element A And a pulling rate of a mixed crystal semiconductor of element B and element v: controlled so as to satisfy a falling rate of a compound semiconductor of element B and element C to be replenished, or

(7) In (1) or (2) or (3) or (4) or (5) or (6), the raw material to be replenished to the melt or solution (eg melt or solution 2) Is cylindrical or prismatic (eg source 3 seen in FIG. 3), or

(8) In the above (1) or (2) or (3) or (4) or (5) or (6) or (7), the melt or solution (for example, melt or solution 2) Characterized in that the cross-sectional area in contact with the melt or solution in the raw material to be replenished with is gradually increased (for example, the truncated quadrangular pyramidal portion 3A in the source 3 shown in FIG. 3), or

(9) In the above (8), the raw material for replenishing the melt or solution should be tapered toward the lower tip (for example, truncated pyramidal shape in the source 3 shown in FIG. 3). Characterized by part 3A), or

(10) In the above (8) or (9),
The raw material to be replenished to the melt or solution (for example, the melt or solution 2) is lowered at a constant lowering speed to replenish (for example, the lowering speed of the source 3 shown in FIG. 3 is 2.56 [m
m / hr] kept constant), or

(11) The above (1) or (2) or (3)
Or (4) or (5) or (6) or (7) or (8)
Alternatively, in (9), based on the result of measuring the mass of the grown multi-element semiconductor (for example, the load cell 8 in FIG. 1), a melt or a solution (for example, melt or solution 2: FIG. 1) is formed. Control the descent rate of the replenishing raw material (for example, Source 3: FIG. 1) (for example, controller 9 and rod 4: FIG. 1)
Or

(12) The above (1) or (2) or (3)
Or (4) or (5) or (6) or (7) or (8)
Alternatively, in (9) or (10) or (11), the means for heating the melt or the solution (for example, the heater 10) is controlled based on the result of measuring the mass of the grown multi-element semiconductor. Or

(13) In the above (12), the means for heating the melt or the solution is controlled to keep the growth interface temperature constant, or

(14) The above (2) or (3) or (4)
Or (5) or (6) or (7) or (8) or (9)
Alternatively, in (10) or (11) or (12) or (13), the element A is a Group 3 element other than the element B, the element B is a Group 3 element other than the element A, and the element C is a Group 5 element. Or

(15) The above (2) or (3) or (4)
Or (5) or (6) or (7) or (8) or (9)
Alternatively, in (10) or (11) or (12) or (13), the element A, the element B and the element C are Group IV elements, or

(16) In the above (15), the element B is the same Group IV element as the element C, and the element A is a Group IV element excluding the element B, or

(17) The above (2) or (3) or (4)
Or (5) or (6) or (7) or (8) or (9)
Alternatively, in (10) or (11) or (12) or (13), the element C is a Group 3 element, the element A is a Group 5 element other than the element B, and the element B is a Group 5 element other than the element A. Or

(18) Crucible (eg, crucible 1: FIG. 1) containing a ternary melt or ternary solution containing element A, element B, and element C (eg melt or solution of InGaAs 2: FIG. 1) And a seed crystal (for example, seed crystal 5: FIG. 1)
And a crystal pulling means (for example, pulling shaft 6: FIG. 1) for pulling and growing a crystal after immersing in the melt or solution and replenishing elements depleted in the melt or solution housed in the crucible. Source feeding means (for example, rod 4 and control device 9, etc .: FIG. 1) for feeding a source (for example, source 3 made of GaAs: FIG. 1) and a multi-element consisting of the grown element A, element B and element C A means for measuring the mass of the system semiconductor (for example, load cell 8: FIG. 1), and controlling the source descending speed and the heater temperature in accordance with the value calculated by the controller based on the measurement result (for example, control And a device 9).

[0063]

FUNCTION Here, the source 3 made of GaAs is InGa.
Let S be the cross-sectional area in contact with the melt 2 made of As, the radius of the growing InGaAs crystal 7 be r, the density of GaAs in ρ _GaAs, and the density V of the crystal 7 made of InGaAs in growing ρ _C. Crystal 7 pulling speed, v is GaA
When lowering speed of the source 3 consisting of _{s, W GaAs = Svρ GaAs ····} (2) W GaAs: the amount of the source of GaAs to replenish ^{_{W C = πr 2 Vρ C ····}} (3) W C : Growth amount (mass increase rate) of the grown InGaAs crystal 7. Substituting this into equation (1),

[0064]

(Equation 3)

It becomes When this equation (4) is transformed,

[0066]

[Equation 4]

It becomes That is, if the source 3 made of GaAs is replenished into the melt 2 at a descending speed satisfying the formula (5) in accordance with the increase of the radius r of the growing crystal 7 made of InGaAs, the melt 2 becomes Since the liquid phase composition does not change, if the temperature at the growth interface is kept constant in this state, the InGaAs shoulder portion 7A having a uniform composition can be grown. Further, if the equation (5) is transformed,

[0068]

(Equation 5)

It becomes That is, when the GaAs source 3 having a narrow tip and a gradually increasing cross-sectional area S is lowered at a constant descent rate v, the GaAs supplied to the melt 2 is replenished.
Therefore, if the temperature of the growth interface is controlled to be constant in that state, the InGaAs crystal 7 having a uniform composition gradually increases in diameter and the shoulder 7
A can grow.

As a result, it is possible to grow the InGaAs crystal 7 having a uniform composition from the shoulder portion 7A to the straight body portion, and prevent the shoulder portion 7A from being polycrystallized or broken due to strain. it can.

Further, since only GaAs is supplied to the melt 2, the surface of the melt 2 is lowered as the crystal 7 grows. Therefore, it is difficult to accurately know the cross-sectional area S in which the source 3 is actually in contact with the liquid surface, except when the source 3 made of GaAs is columnar or prismatic.

Therefore, the mass of the InGaAs crystal 7 is measured by using the load cell 8, the difference ΔW _C between the set mass increase amount and the measured value is obtained, and the descent rate v of the source 3 or heating By feeding back to the heater 10, ΔW _C can be made zero.

[0073]

【Example】

First Example Inner diameter 80 [m in the pull-up growth apparatus shown in FIG.
m] in the crucible 1 of 87.67 [g] and In
After As was introduced in 192.33 [g], the crucible 1 was heated to 1380 [° C.] by the heater 10 to obtain InGaA.
A melt 2 composed of s is generated.

The seed crystal 5 has a length of 30 mm and a diameter of 5
The source 3 is made of columnar GaAs having a length of 50 mm and a transverse section of 10 mm! □.

The seed crystal 5 fixed to the crystal pulling shaft 6 is brought into contact with the melt 2 while lowering the temperature so that the interface temperature becomes 1113 [° C.] and maintaining the temperature. Further, the source 3 fixed to the rod 4 is brought into contact with the melt 2.

After that, the source 3 is lowered by a predetermined program, which needs to follow the descent program shown in FIG. 2, so that FIG. 2 will be described next.

FIG. 2 is a diagram showing a source descent program, in which the horizontal axis represents time [hr] and the vertical axis represents descent speed [mm / hr].

The growth is initially performed by bringing the source 3 into contact with the melt 2 and keeping the same state before the start of growth, that is, 0 [mm /
h], and then, the crystal pulling shaft 6 is pulled up and lowered at 0.32 [mm / h] from the time when the growth is started.

Specifically, as described above, after bringing the source 3 into contact with the melt 2, the descending speed is increased according to the program shown in FIG. 2 and the crystal pulling shaft 6 is rotated at 40 [rpm]. While pulling, it is pulled up at 2 [mm / hr].

At this time, the mass increase rate W _C of the InGaAs crystal 7 is 0.21 [g / hr] to 3.34.
[G / hr] Therefore, if feedback is applied to the descending speed of the source 3 so that the diameter of the crystal 7 increases linearly from 5 [mm] φ to 20 [mm] φ over 10 [hours], the melt The deterioration of the surface of No. 2 can be corrected.

As a result, as set by the equation (5),
The crystal 7 has a diameter of 5 after 10 hours from the pulling up.
From [mm] φ to 20 [mm] φ, mixed crystal ratio In _0.1 G
The shoulder 7A having a uniform composition of a _0.9 As could be grown.

Second Embodiment In the first embodiment, the source 3 made of GaAs was supplied by increasing the descending speed with time, but in the second embodiment, the same effect can be obtained by selecting the shape of the source 3. To get

FIG. 3 is a perspective view of a main portion for explaining the shape of the source 3 used in the second embodiment. As is clear from the figure, the source 3 is composed of a truncated quadrangular pyramid portion 3A and a prismatic portion 3B, and the tip of the truncated quadrangular pyramid portion 3A has a size of 2.5 mm. The rear end of the prismatic portion 3B has a size of 10 [mm] □, the length of the truncated quadrangular pyramid portion 3A is 25 [mm], and the length of the prismatic portion 3B is also 25 [mm]. Has become.

In the second embodiment, the pulling speed of the crystal 7 is 1 [mm / hr], and the descending speed of the source 3 is 2.5.
6 [mm / hr] is kept constant, and the mass increase rate W _C of the InGaAs crystal 7 is 0.10 [g / hr] to 1.67 [g / hr], and therefore the diameter of the crystal 7 is 5 [ m
If the descent rate of the source 3 is fed back so as to increase linearly from m] φ to 20 [mm] φ over 10 [hours], it is possible to correct the decrease in the surface of the melt 2.

As a result, as set by the equation (5),
It took 10 hours from seeding that the crystal 7 had a diameter of 5
From [mm] φ to 20 [mm] φ, mixed crystal ratio In _0.1 G
The shoulder 7A having a uniform composition of a _0.9 As could be grown.

[0086]

In the pull-up growth method and pull-up growth apparatus according to the present invention, a multi-component semiconductor melt or solution consisting of two or more raw materials is replenished with one or more of the above raw materials. The multi-component semiconductor is grown by pulling the seed crystal immersed in the melt or the solution by replenishing while controlling the speed as a function of time.

According to the above-mentioned structure, when the seed crystal is grown by immersing the seed crystal in the melt or the solution of the multi-component semiconductor and then pulling it up, the seed crystal is enlarged until it has a required diameter. During the growth of the part, the so-called shoulder part, since the raw material which will be depleted is replenished, the composition of the shoulder part does not have a gradient, so that the growth is achieved. It is possible to eliminate the risk that a large lattice distortion will occur in the crystal, and as a result, the crystal will be polycrystallized, and the straight body portion of the crystal thereafter will be polycrystallized.

[Brief description of drawings]

FIG. 1 is a principal part explanatory view showing a pulling growth apparatus for carrying out a pulling growth method of the present invention.

FIG. 2 is a diagram showing a source descent program.

FIG. 3 is a perspective view of a main part for explaining the shape of a source 3 used in the second embodiment.

FIG. 4 is a principal part explanatory view showing a pulling growth apparatus for explaining a conventional technique relating to pulling growth of a ternary compound semiconductor crystal.

FIG. 5 is a state diagram of In _x Ga _1-x As.

FIG. 6 is a diagram showing the relationship between the solidification rate of In _x Ga _1-x As and the composition x of the solid phase.

[Explanation of symbols]

1 crucible 2 melt (or solution) 3 compound semiconductor source for replenishing melt 3A truncated square pyramidal part 3B prismatic part 4 rod for inserting and removing the source 3 into the melt 2 seed crystal 6 Pulling shaft for immersing seed crystal 5 in melt 2 and then pulling it 7 Growing compound semiconductor crystal 7A Shoulder portion 8 of crystal 7 Load cell for measuring the weight of crystal 7 Control device 10 Heating heater

Claims (18)

[Claims] 1. A melt or solution of a multi-component semiconductor composed of two or more raw materials is supplied to the melt or solution while controlling the replenishment rate of one or more of the raw materials as a function of time. A pull-up growth method comprising pulling a seed crystal immersed in a solution to grow the multi-component semiconductor. 2. A multi-element semiconductor composed of two or more raw materials is a multi-element semiconductor composed of an element A, an element B and an element C, and a raw material supplied to a melt or a solution is an element B and an element C.
The pull-up growth method according to claim 1, wherein the pull-up growth method is a semiconductor made of. 3. The pull-up growth method according to claim 1, wherein the replenishment of the raw material to the melt or the solution is started from the time when the seed crystal is brought into contact with the melt or the solution. 4. The pull-up growth method according to claim 1, 2 or 3, wherein a shoulder portion for enlarging a crystal from a seed crystal to a desired diameter is prepared while supplying a raw material to a melt or a solution. 5. The pull-up growth method according to claim 1, wherein the crystal is produced while maintaining the growth interface temperature constant. 6. The descending rate of a compound semiconductor composed of element B and element C, which is a raw material to be replenished, in which a liquid composed of a multi-element semiconductor composed of element A, element B and element C is a melt, Number 1] Here, X _L: mole ratio of the element A in the melt X _S: mole fraction M _AC of the element A ternary mixed crystal in the semiconductor grown: a compound semiconductor of element A and element C molecular weight M _BC : Molecular weight of compound semiconductor of element B and element C ρ _BC : Density of compound semiconductor of element B and element ρ _C : Density of mixed crystal semiconductor of grown element A, element B and element S S: Supply Area where compound semiconductor consisting of element B and element C contacts the melt surface r: radius of mixed crystal semiconductor of grown element A, element B and element C V: grown element A, element B and element C 6. The pulling growth method according to claim 1, wherein the pulling rate of the mixed crystal semiconductor is v: The pulling rate of the compound semiconductor of the element B and the element C to be replenished is controlled according to the dropping rate. . 7. The melt or the raw material to be replenished to the solution has a cylindrical or prismatic shape.
Alternatively, the pulling growth method described in 3 or 4 or 5 or 6. 8. The cross-sectional area in contact with the melt or solution in the raw material to be replenished with the melt or solution is gradually increased, or 1 or 2 or 3 or 4 or 5 or 6 or 7 The described pull-up growth method. 9. The pull-up growth method according to claim 8, wherein the raw material for replenishing the melt or solution is tapered toward the lower end. 10. The pull-up growth method according to claim 8 or 9, wherein the raw material to be replenished to the melt or solution is lowered at a constant descent rate to replenish. 11. The descending speed of the raw material supplied to the melt or solution is controlled based on the result of measuring the mass of the grown multi-element semiconductor. 6 or 7 or 8 or 9
The described pull-up growth method. 12. The means for heating the melt or the solution is controlled based on the result of measuring the mass of the grown multi-element system semiconductor.
Or 5 or 6 or 7 or 8 or 9 or 10
Alternatively, the pulling growth method described in 11. 13. The pull-up growth method according to claim 12, wherein the growth interface temperature is kept constant by controlling the means for heating the melt or the solution. 14. Element A is a Group 3 element other than element B, and element B
The element according to claim 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13, wherein is a Group 3 element other than element A and element C is a group 5 element. How to grow. 15. The element A, the element B, and the element C are group IV elements, and the elements are 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13. How to grow. 16. The pull-up growth method according to claim 15, wherein the element B is the same Group IV element as the element C, and the element A is a Group IV element excluding the element B. 17. The element C is a Group 3 element, the element A is a Group 5 element other than the element B, and the element B is a Group 5 element other than the element A. 2. 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 18. A crucible containing a ternary melt or ternary solution containing element A, element B and element C, and a seed crystal that is held and dipped in the melt or solution before pulling and growing the crystal. Crystal pulling means, source feeding means for feeding a source for replenishing an element that is depleted in the melt or solution contained in the crucible, and a multi-element semiconductor composed of the grown element A, element B and element C And a means for controlling the source descending speed and the heater temperature in accordance with the value calculated by the controller based on the measurement result.