TWM461635U - Crucible unit for crystal growth - Google Patents

Description

Tantalum unit for long crystals

The present invention relates to a crucible unit, and more particularly to a unit for a crystal.

The grain size and morphology of polycrystalline Si affect the performance of solar cells. A uniform silicon wafer size (eg, about 10 mm) and a uniform polysilicon wafer (Si wafer) contributes to improving the photon-to-current conversion efficiency (PCE) of the solar cell. However, it is well known to those skilled in the art that a grain size that is moderate and uniform in grain size is primarily dependent on whether the initial nucleation of the ingot is properly controlled during growth.

The technique for growing a polycrystalline germanium is simply (not shown), which is mainly to place a raw material in a quartz crucible and heat the crucible at a high temperature to cause the crucible material in the quartz crucible. Melting into a molten soup at a high temperature; further, absorbing the heat through the fixed heat block disposed under the quartz crucible, so that the molten soup gradually solidifies from the bottom of the quartz crucible to grow upward The polycrystalline germanium is emitted.

Those skilled in the art are aware of the crystal The normal growth rate (Rn=c.ΔT) is linear with the undercooling (ΔT) of the melt. The degree of subcooling (ΔT) of the so-called melt soup refers to the temperature difference between the nucleus of crystalline and the inside and outside of the quartz crucible during the nucleation phase of the directional solidification growth. Once the thickness of the bottom of the quartz crucible is the same, the temperature difference between the inside and outside of the quartz crucible is the same. Therefore, during the nucleation period of the polycrystalline twins during the directional solidification growth process, the bottom of the quartz crucible will randomly form a random distribution of crystal nuclei. It is also because of the disordered distribution of crystal nuclei that the crystal nuclei tend to be bound by other similar grains in the process of grain growth, so there is not enough free growth space, so that the growth of crystal grains is limited, resulting in the final The grain size is not uniform. In order to solve the problem of uneven grain size, those skilled in the art have also proposed some solutions in recent years.

Referring to Fig. 1 and Fig. 2, the utility model patent of the CN201962402 U authorized bulletin No. discloses a quartz crucible for polycrystalline silicon casting. The polycrystalline silicon crucible for quartz crucible 1 comprises: a bottom wall 11 and a surrounding wall 12 surrounding the bottom wall 11, and the bottom wall 11 and the surrounding wall 12 together define a receiving material (not shown). The accommodation space is 10. The bottom wall 11 is formed with a plurality of conical recesses 111 recessed from an upper surface of the bottom wall 11 at intervals. The main purpose of the design of each conical pit 111 of the quartz crucible 1 for polycrystalline tantalum casting is to form coarse and uniform niobium grains, thereby improving the photoelectric conversion efficiency of the polycrystalline silicon solar cell sheet.

However, the conical recess 111 in the bottom wall 11 is mostly designed to have a sharp profile; therefore, the stress concentration factor of the bottom wall 11 (stress Concentration factor) is high. When the polycrystalline tantalum cast quartz crucible 1 is used to produce a grown twine ingot, the bottom wall 11 is liable to induce cracks due to a difference in thermal expansion coefficient between the material and the tantalum melt, thereby causing cracks. The polycrystalline crucible is broken with a quartz crucible 1 and causes a risk of overflowing the crucible.

Referring to Fig. 3 and Fig. 4, the new patent of the Republic of China No. M444886 certificate discloses a casting mold 2 for manufacturing a twin casting. The casting mold 2 for manufacturing a twine casting mold comprises: a bottom wall 21 and a surrounding wall 22 surrounding the bottom wall 21, and the bottom wall 21 and the surrounding wall 22 together define a receiving melting point The accommodation space of the soup (not shown) is 20. The bottom wall 21 is formed with a plurality of arcuate recesses 211 recessed from the upper surface of the bottom wall 21 at intervals. wherein the arcuate recesses 211 are between 5 mm and 10 mm in size. And the distance between two adjacent arcuate dimples 211 is between 0.1 mm and 10 mm. The casting mold 2 for manufacturing the twin-crystal casting shovel mainly utilizes the arc-shaped recesses 211 of the bottom wall 21 to prevent the bottom wall 21 from inducing cracks during the manufacture of the twin-crystal casting boring, thereby reducing the simmering soup. The risk of overflow.

However, the arcuate dimples 211 are filled with the bottom wall 21 of the casting mold 2; oppositely, the bottom of the finally completed twin-shaped casting crucible is also formed at the corresponding portion of each of the arc-shaped dimples 211, and a plurality of The appearance is complementary to the arcuate bumps of each of the arcuate recesses 211 (not shown). Therefore, the arc-shaped bumps which are filled on the bottom of the twin-crystal cast enamel also cause the twin-crystal cast slab to undergo twinning during the longitudinal squaring process due to the internal stress remaining in each of the curved bumps.碇 cracked. Therefore, the design of the arcuate dimples 211 invisibly reduces the effective utilization of the twinned casts.

According to the above description, the ruthenium structure for the crystal growth is improved so that the crystal nucleus formed during the nucleation period of the crystal nucleus is more uniformly distributed at the bottom of the crucible, and the growth space of the crystal nucleus during the grain growth process is increased to avoid The growth of crystal grains is limited, and the effective use rate of crystal grains is also improved, which is a subject to be solved by those skilled in the technical field.

Therefore, it is an object of the present invention to provide a germanium unit for a crystal growth.

Therefore, the novel germanium unit for the growth of the crystal is used for growing a polycrystalline germanium. The polycrystalline silicon wafer is sequentially cut longitudinally into a plurality of bricks and slicing into a plurality of wafers. The surface of each wafer is substantially rectangular in shape, each wafer surface has a pair of first side lengths and a pair of second side lengths, the pair of first side lengths and the pair of second side lengths being substantially parallel to a first direction, respectively And a second direction. The germanium unit for the crystal growth includes: a bottom wall and a surrounding wall. The bottom wall has a two-dimensional array of platform zones having a plurality of cells. The units are sequentially disposed along the first direction and sequentially disposed along the second direction. Each unit has a first platform area and a second platform area substantially surrounding the first platform area corresponding thereto. The surrounding wall extends upward from a peripheral edge of the bottom wall to surround the bottom wall and defines an accommodation space together with the bottom wall.

The shape of each unit of the two-dimensional platform area array is substantially a rectangle, and each unit has a pair of first side lengths parallel to the first direction, and a pair of second side lengths parallel to the second direction. . The first side length and the second side length of each wafer surface are respectively larger than the two-dimensional array of the land area The first side length and the second side length of each unit are long, and the first side length of each wafer surface is substantially an integral multiple of the first side length of each unit, and the second side length of each wafer surface is substantially the second of each unit An integer multiple of the side length.

The first platform area and the second platform area of each unit of the two-dimensional platform area array respectively have a first thickness T ₁ and a second thickness T ₂ along a thickness direction of the bottom wall, T ₁ < T ₂ .

The effect of the novel is that the thickness difference between each first platform region and each second platform region of the two-dimensional platform region array of the bottom wall is such that the crystal nucleus formed by the crystal nucleation during the nucleation period can be uniformly distributed. And the first side length of the first platform region of each unit and the integral multiple of the second side length are substantially equal to the first side length and the second side length of each wafer, respectively, to prevent cracking of the crystal wafer during longitudinal cutting, and Improve the effective use of wafers.

3‧‧‧ bottom wall

31‧‧‧Two-dimensional platform area array

311‧‧ units

3111‧‧‧First platform area

3112‧‧‧Second platform area

32‧‧‧ surrounding area

4‧‧‧ wall

40‧‧‧ accommodating space

6‧‧‧Polycrystalline wafer

61‧‧‧矽crystalline brick

611‧‧‧矽 wafer

X‧‧‧ first direction

Y‧‧‧second direction

Z‧‧‧ Thickness direction of the bottom wall

T ₁ ‧‧‧first thickness

T ₂ ‧‧‧second thickness

S ₁ ‧‧‧first side length

S ₂ ‧‧‧Second side length

s ₁ ‧‧‧first side length

s ₂ ‧‧‧Second side length

u ₁ ‧‧‧first diagonal length

u ₂ ‧‧‧Second diagonal length

Θ‧‧‧ diagonal

Other features and effects of the present invention will be apparent from the following description of the drawings, wherein: FIG. 1 is a perspective view showing a polycrystalline silicon casting used in the utility model patent publication CN201962402 U. Fig. 2 is a partial cross-sectional view showing the conical pit inside the quartz crucible for polycrystalline crucible casting; Fig. 3 is a top plan view showing a novel disclosed in the new patent No. M444886 certificate of the Republic of China for A casting mold for manufacturing a twin-shaped cast iron; FIG. 4 is a partial cross-sectional view taken along line IV-IV of FIG. 3, illustrating the arc-shaped pits for the inside of a casting mold for manufacturing a polycrystalline cast strand; Figure 5 is a top plan view showing a first preferred embodiment of the present invention for a long crystal germanium unit; Figure 6 is a partial cross-sectional view taken along line VI-VI of Figure 5, illustrating the novel A two-dimensional array of platform regions of a bottom wall of a first preferred embodiment; FIG. 7 is a partial bottom perspective view showing a polycrystalline silicon germanium produced by using the germanium unit of the first preferred embodiment of the present invention, The appearance shape after longitudinally cutting into a twinned brick and longitudinally slicing into a tantalum wafer, and the appearance of the bottom of the polycrystalline twine; FIG. 8 is a partial enlarged view of FIG. 5, illustrating the first A detailed structure of each unit of the two-dimensional land area array of the bottom wall of the preferred embodiment; FIG. 9 is a top plan view showing a second preferred embodiment of the present invention for a germanium unit of a long crystal; and FIG. Figure 9 is a partially enlarged schematic view showing the detailed structure of each unit of the two-dimensional land area array of the bottom wall of the second preferred embodiment of the present invention.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

Referring to Figures 5, 6, and 7, a first preferred embodiment of the present invention for a grown germanium unit is for growing a polycrystalline germanium 6. As shown in FIG. 7, the polycrystalline twins 6 are sequentially cut vertically into a plurality of twinned bricks 61 in the longitudinal direction, and are laterally sliced into a plurality of tantalum wafers 611. The shape of the surface of each of the germanium wafers 611 is substantially a rectangle. The surface of each of the germanium wafers 611 has a pair of first side lengths S ₁ and a pair of second side lengths S ₂ . The pair of first side lengths S ₁ and the pair of second side lengths S ₂ are substantially parallel to a first direction X and a second direction Y, respectively. The tantalum unit for the growth of the first preferred embodiment of the present invention comprises a bottom wall 3 and a surrounding wall 4. It should be added here that any technician with a mathematical background should know that a rectangle is defined as a quadrilateral with four vertex angles of 90 degrees; therefore, both rectangles and squares belong to the definition of rectangles in the present invention.

Referring to Figure 8, and with reference to Figures 6 and 7, the bottom wall 3 has a two-dimensional array of platform regions 31 and a surrounding region 32. The two-dimensional platform area array 31 has a plurality of cells 311. The units 311 are sequentially disposed along the first direction X and sequentially disposed along the second direction Y. Each unit 311 has a first platform area 3111 and a second platform area 3112 substantially surrounding the first platform area 3111 to which it corresponds. The surrounding wall 4 extends upward from a peripheral edge of the bottom wall 31 to surround the bottom wall 3 and together with the bottom wall 3 defines an accommodating space 40.

The shape of each unit 311 of the two-dimensional platform area array 31 is substantially a rectangle. Each unit 311 has a pair of first side lengths s ₁ parallel to the first direction X and a pair of second side lengths s ₂ parallel to the second direction Y. The first side length S ₁ and the second side length S _{2 of the} surface of each of the tantalum wafers 611 are larger than the first side length s ₁ and the second side length s ₂ of each unit 311 of the two-dimensional platform area array 31, respectively. The first side length S _{1 of the} surface of each of the germanium wafers 611 is substantially an integral multiple of the first side length s ₁ of each of the cells 311, and the second side length S _{2 of the} surface of each of the germanium wafers 611 is substantially the second side of each of the cells 311. An integer multiple of s ₂ long.

The first platform region 3111 and the second platform region 3112 of each unit 311 of the two-dimensional platform region array 31 have a first thickness T ₁ and a second thickness T along a thickness direction Z of the bottom wall 3 respectively. ₂ , T ₁ <T ₂ . Preferably, T ₁ <19 mm, T ₂ >19 mm, and the second thickness T ₂ of the second land region 3112 of each unit 311 of the two-dimensional platform region array 31 is substantially equal. More preferably, T ₁ is between 14 mm and 18 mm and T ₂ is between 20 mm and 24 mm. The surrounding area 32 surrounds the two-dimensional array of platform regions 31 such that the distance between the array of two-dimensional platform regions 31 to the surrounding walls 4 is between 25 mm and 28 mm.

The shape of the first platform area 3111 of each unit 311 of the two-dimensional platform area array 31 is substantially a rhombic, and each of the first platform areas 3111 has a first direction X and a second direction Y, respectively. The first diagonal length u ₁ and a second diagonal length u ₂ , the first side length S _{1 of the} surface of each of the germanium wafers 611 is substantially an integer of the first diagonal length u ₁ of each of the first land regions 3111 The second side length S _{2 of the} surface of each of the wafers 611 is substantially an integer multiple of the second diagonal length u ₂ of each of the first land regions 3111. Preferably, the first platform region 3111 of each unit 311 of the two-dimensional platform region array 31 has a pair of diagonal angles θ along the second direction Y, and the angles of the respective diagonal angles θ are between 85 and 95. Degree.

It should be additionally noted that the shape and size of each of the first platform regions 3111 distributed on the bottom wall 3 of the first preferred embodiment are mainly based on the current output commonly produced in the parent crystal factory. The shape and size of the surface of the wafer 611 are designed. For the surface shape and size of the tantalum wafer 611 commonly used in various parent crystal factories, it is preferably a square having a side length of 155 mm to 160 mm, and the twin crystal bricks 61 are 5×5. The two-dimensional array is arranged orthogonally. Therefore, in the first preferred embodiment of the present invention, the angles of the respective diagonal angles θ of the first land regions 3111 are 90 degrees, and the rectangles of the surfaces of the respective wafers 611 and the arrays of the two-dimensional platform region array 31 are The rectangle of the unit 311 is a square, and the side lengths S ₁ and S ₂ of the square of the surface of each of the tantalum wafers 611 are between 157 mm and 158 mm, and the side length of the square of the surface of each of the tantalum wafers 611 is the unit 311. The first diagonal length u _{1 of the} first platform region 3111 (ie, equal to s ₁ ) is five times longer than the second diagonal length u ₂ (ie, equal to s ₂ ).

It can be seen from the foregoing description that in the first preferred embodiment of the present invention, the first platform area 3111 of each unit 311 of the two-dimensional platform area array 31 of the bottom wall 3 is the second platform area corresponding thereto. Surrounded by 3112, the second thickness T ₂ of each second platform region 3112 is substantially equal, and T ₁ <T ₂ ; in addition, the shape of each unit 311 and the shape of each first platform region 3111 are square and rhombic, respectively, and The side length of the square of the surface of each of the germanium wafers 611 is the first diagonal length u ₁ of the first land area 3111 of each unit 311 (ie, equal to s ₁ ) and the second diagonal length u ₂ (ie, equal to 5 times s ₂ ). In other words, the first land area 3111 (each of which is a diamond-shaped recessed area) of each unit 311 of the two-dimensional platform area array 31 is respectively arranged with four diamond-shaped convex areas (that is, each diamond-shaped convex area is phased) The adjacent second platform area 3112 is formed). Therefore, when the first preferred embodiment of the present invention is used to grow the polycrystalline germanium 6, as shown in FIG. 7, the bottom of the polycrystalline germanium 6 corresponds to each of the two-dimensional terrace region array 31. A platform area 3111 (each of which is a diamond-shaped recessed area) and each of the second platform areas 3112 (each of which is a diamond-shaped convex area) are respectively corresponding to a plurality of diamond-shaped convex regions and a plurality of diamond-shaped concave regions which are arranged in two dimensions.

In addition, the first preferred embodiment of the present invention further comprises a tantalum nitride (Si ₃ N ₄ ) coating (not shown). The tantalum nitride coating covers an upper surface of the bottom wall 3 and an inner surface of the surrounding wall 4, the main purpose of which is to assist in demolding the polycrystalline silicon germanium 6. The tantalum nitride coating is not the technical focus of the present invention, and will not be further described herein. However, it should be further noted that, in order to facilitate coating the tantalum nitride coating on the two-dimensional platform area array 31, the above-mentioned respective rhombic concave regions and the respective rhombic convex regions of the first preferred embodiment of the present invention. At each diagonal θ (90 degrees) and at two opposite angles (also 90 degrees) along the first direction X, it is further processed into a curved surface.

Referring to FIG. 9 and FIG. 10 (and with reference to FIG. 7), the second preferred embodiment of the present invention for a germanium unit of a long crystal is substantially the same as the first preferred embodiment, the difference being that The angles of the respective diagonal angles θ of the first platform regions 3111 of the second preferred embodiment of the present invention are between 115 degrees and 125 degrees. In the second preferred embodiment of the present invention, the angle of each diagonal θ is 120 degrees, and the rectangle of the surface of each of the 矽 wafers 611 and the rectangle of each unit 311 of the two-dimensional platform area array 31 are rectangular; The first side length S ₁ and the second side length S ₂ of the rectangle of the surface of the germanium wafer 611 are respectively 157 Mm to 158 Between mm and 157 mm and 158 mm, and the first side length S ₁ and the second side length S _{2 of the} surface of each of the dies 611 are the first diagonal of the first land area 3111 of each unit 311, respectively. The length u ₁ is 5 times longer than the second diagonal length u ₂ .

When the polycrystalline silicon germanium 6 is grown by actually using the germanium unit of the preferred embodiment of the present invention (hereinafter, only FIG. 6 is exemplified, there are components such as a crystal growth furnace, a crucible raw material, a directional heat-receiving block, and a crucible melting soup. , said below Not shown in Fig. 6), a raw material is pre-placed in the accommodating space 40 of each 坩埚 unit, and each 坩埚 unit is placed in a crystal growth furnace, and a heating unit in the crystal growth furnace is utilized. The raw material of the crucible is heated to melt the crucible material into a crucible. Further, the crucible melt is formed in the vertical direction (ie, the thickness direction Z of the bottom wall 3) through a certain direction of heat extraction under the respective unit to form a directional solidification growth.

The preferred embodiments of the present invention utilize different thickness differences between the first platform regions 3111 of the bottom walls 3 and the second platform regions 3112 to provide different degrees of subcooling for the nucleation nucleation nucleation. (ΔT), causing the twin crystal nucleus to be uniformly distributed on the bottom wall 3, so that the crystallographic grains of different crystallographic directions can have different growth rates to compete with each other, and the crucible is adjacent to the center of the bottom wall 3 The majority of the grains are tantalum grains (<10 mm) of uniform size and small size. However, it should be additionally noted here that crystals having a small crystal grain have a relatively high grain boundary. For grain growth, high-density grain boundaries can attract defect concentration by their own stress field, which induces dislocation to be offset by slip or climb mechanisms. The formation of the difference row and thereby the release of thermal stress. It can be seen from the foregoing description that during the growth of the directional solidification, the uniformly uniform and small ruthenium grains distributed at the bottom of the polycrystalline ruthenium 6 contribute to suppress the generation of the difference row, so that the Crystals grown above the smaller and uniform germanium grains can achieve larger (about 10 mm) and uniform germanium grains. Therefore, it contributes to improving the photoelectric conversion efficiency of the solar cell.

In another aspect, the preferred embodiment of the present invention has an integer multiple of the first and second diagonal lengths u ₁ , u ₂ of each of the first land regions 3111 (each being a diamond shaped recess) on the bottom wall 3, Respectively equal to the first and second sides S ₁ , S _{2 of the} surface of each of the germanium wafers 611, such that the bottom of the polycrystalline germanium 6 corresponds to each of the first land regions 3111 (each being a diamond shaped recess) and each of the second platforms The regions 3112 (each of which are diamond-shaped convex regions) respectively form a diamond-shaped convex region and a diamond-shaped concave region. Therefore, when the polycrystalline twins 6 are vertically cut in the longitudinal direction, the cutting lines thereof can be accurately positioned in the respective rhombic recessed regions at the bottom of the polycrystalline twins 6, and the diamond-shaped bumps at the bottom of the polycrystalline twins 6 are relatively reduced. The probability of the region is such that the polycrystalline germanium 6 avoids the problem of crystal germanium cracking caused by residual internal stress, thereby improving the effective use rate of the polycrystalline germanium.

It is further worth mentioning that the second preferred embodiment of the present invention makes each diagonal angle θ of each first platform region 3111 120 degrees, which reduces the free energy difference of the twin crystal nucleation during nucleation, and is also beneficial. The ruthenium grains in each crystal orientation achieve a uniform growth rate during crystal growth, so that the ruthenium grains of each crystal orientation uniformly compete with each other during crystal growth. Therefore, the uniformity of the germanium grain size of the polycrystalline germanium 6 is further improved.

In summary, the present invention is applied to a germanium unit of a long crystal, on the one hand, the thickness difference between each first plateau region 3111 and each second plateau region 3112 is utilized, so that the twin nucleus of the polycrystalline twins 6 can be uniformly distributed. In the bottom wall 3, and the different crystal orientation of the germanium grains can have different growth rates to compete with each other, so that the polycrystalline germanium 6 has a medium and uniform grain size, and on the other hand, the novel In the preferred embodiment, the bottom of the polycrystalline silicon germanium 6 is corresponding to each of the first and second land regions 3111 and 3112 (each of which is a diamond-shaped concave region and a diamond-shaped convex region), which respectively form a diamond-shaped convex region and a diamond-shaped concave region. When the polycrystalline twins 6 are vertically cut in the longitudinal direction, the probability that the cutting line is located at each of the rhombic protrusions at the bottom of the polycrystalline germanium 6 can be reduced, so that the polycrystalline twins 6 can avoid the cracking of the crystal grains caused by the residual internal stress. The problem, thereby increasing the effective use rate of the polycrystalline twins 6, can indeed achieve the object of the present invention.

However, the above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, that is, the simple equivalent changes and modifications made in accordance with the scope of the present patent application and the contents of the patent specification, All remain within the scope of this new patent.

31‧‧‧Two-dimensional platform area array

311‧‧ units

3111‧‧‧First platform area

3112‧‧‧Second platform area

32‧‧‧ surrounding area

4‧‧‧ wall

X‧‧‧ first direction

Y‧‧‧second direction

S ₁ ‧‧‧first side length

S ₂ ‧‧‧Second side length

S ₁ ‧‧‧first side length

S ₂ ‧‧‧Second side length

u ₁ ‧‧‧first diagonal length

u ₂ ‧‧‧Second diagonal length

Θ‧‧‧ diagonal

Claims (10)

A germanium unit for a long crystal is used for growing a polycrystalline germanium, which is sequentially cut into a plurality of crystal bricks in a longitudinal direction and laterally sliced into a plurality of wafers, and the shape of each wafer surface is substantially a rectangle having a pair of first side lengths and a pair of second side lengths, wherein the pair of first side lengths and the pair of second side lengths are substantially parallel to a first direction and a second direction, respectively The germanium unit for the crystal growth comprises: a bottom wall having a two-dimensional array of platform regions, the two-dimensional array of platform regions having a plurality of cells, the cells being sequentially disposed along the first direction and along the first The two directions are sequentially arranged, each unit has a first platform area and a second platform area substantially surrounding the first platform area corresponding thereto; and a surrounding wall extending upward from a peripheral edge of the bottom wall to surround the a bottom wall, and defining a receiving space together with the bottom wall; wherein each unit of the two-dimensional platform area array has a shape substantially rectangular, and each unit has a pair of first sides parallel to the first direction Long, and a pair parallel to the The second side length of the two directions, the first side length and the second side length of each wafer surface are respectively larger than the first side length and the second side length of each unit of the two-dimensional platform area array, and the surface of each wafer The first side length is an integer multiple of the first side length of each unit, and the second side length of each wafer surface is substantially an integer multiple of the second side length of each unit; and wherein each of the two-dimensional platform area arrays The first platform area and the second platform area of the unit respectively have a first thickness (T ₁ ) and a second thickness (T ₂ ) along the thickness direction of the bottom wall, T ₁ <T ₂ . The germanium unit for a long crystal according to claim 1, wherein the second thickness (T ₂ ) of the second land region of each unit of the two-dimensional platform region array is substantially equal. The tantalum unit for crystal growth according to claim 2, wherein T ₁ is between 14 mm and 18 mm, and T ₂ is between 20 mm and 24 mm. The 坩埚 unit for a long crystal according to claim 3, wherein a shape of the first land area of each unit of the two-dimensional platform area array is substantially a diamond shape, and each of the first platform areas is along the first direction The second direction has a first diagonal length and a second diagonal length, and the first side length of each wafer surface is substantially an integer multiple of the first diagonal length of each first platform region, and each The second side length of the wafer surface is substantially an integer multiple of the second diagonal length of each of the first land regions. The 坩埚 unit for a long crystal according to claim 4, wherein the first land area of each unit of the two-dimensional platform area array has a pair of diagonals along the second direction, and the angles of the diagonals are Between 85 and 95 degrees. The germanium unit for a long crystal according to claim 5, wherein an angle of each diagonal is 90 degrees, and a rectangle of each wafer surface and a rectangle of each unit of the two-dimensional land area array are a square. The tantalum unit for crystal growth according to claim 6, wherein the square side length of each wafer surface is between 157 mm and 158 mm The side length of the square of each wafer surface is the first diagonal length of the first land area of each unit and five times the length of the second diagonal line. The 坩埚 unit for a long crystal according to claim 4, wherein each of the first platform regions of the two-dimensional platform region array has a pair of diagonals along the second direction, and the angles of the diagonals are 115 degrees to 125 degrees. The germanium unit for a long crystal according to claim 8, wherein the angle of each diagonal is 120 degrees, and a rectangle of each wafer surface and a rectangle of each unit of the two-dimensional land area array are a rectangle. The 坩埚 unit for a long crystal according to claim 9, wherein the first side length and the second side length of the rectangle of each wafer surface are respectively 157 Mm to 158 Between mm and 158 mm, and the first side length and the second side length of each wafer surface are respectively the first diagonal length and the second diagonal length of the first land area of each unit 5 times.