CN218842400U

CN218842400U - Quartz ring for improving oxygen content of heavily antimony-doped silicon single crystal

Info

Publication number: CN218842400U
Application number: CN202120487013.1U
Authority: CN
Inventors: 潘金平; 肖世豪; 张立安; 吴雄杰; 沈益军; 饶伟星; 苏文霞; 白超; 王志雄; 陈伯弘
Original assignee: Zhejiang Haina Semiconductor Co ltd
Current assignee: Zhejiang Haina Semiconductor Co ltd
Priority date: 2021-03-08
Filing date: 2021-03-08
Publication date: 2023-04-11
Anticipated expiration: 2031-03-08

Abstract

The utility model relates to the technical field of silicon single crystals, in particular to a quartz ring for improving the oxygen content of heavily antimony-doped silicon single crystals. The quartz ring comprises an anti-floating framework, wherein quartz is fixed on the anti-floating framework, and the quartz wraps the anti-floating framework to form a quartz ring body. Above-mentioned structure, when using, owing to increased the anti-frame that floats, the bigger material of cooperation density ratio, for example copper and molybdenum, so has had obvious anti-floating ability, can guarantee that the quartz ring body is in the crucible bottom always when using, the ring body part has adopted trapezium structure, the area of contact of quartz ring body and silicon solution has not only been increased, and the effectual water conservancy diversion of conical surface ability of outer rampart, reduce the influence of the ascending power of fluid, the inner rampart then increases the pressure of cassia silica solution to quartz ring body bottom, the cooperation increases the dissolving hole, the area of contact of quartz ring body and silicon solution has not only been increased, and guaranteed that the quartz ring body is stable arrange the crucible bottom in and not influenced by buoyancy and silicon solution flow.

Description

Quartz ring for improving oxygen content of heavily antimony-doped silicon single crystal

Technical Field

The utility model relates to the technical field of silicon single crystals, in particular to a quartz ring for improving the oxygen content of heavily antimony-doped silicon single crystals.

Background

As is known, the oxygen content of the heavily-doped antimony-silicon single crystal is about 40 percent lower than that of other conventional single crystals, on one hand, oxygen in silicon is used for absorbing heavy metal impurities (i.e. internal impurities) on the surface of a silicon wafer in the device thermal process; on the other hand, the thermal energy formed by interstitial oxygen in silicon also influences the resistivity and the uniformity of a silicon wafer, the oxygen behavior in the crystal has a close relation with micro defects, and the oxidation stacking faults formed by the micro defects on the silicon surface in the thermal oxidation process of a device directly influence the yield of the device, so that the performance of the device is influenced by over or under the oxygen content in the silicon single crystal.

The invention patent (US 4545849) discloses a method for increasing the contact area of silicon melt and quartz, designs a quartz ring, and puts the quartz ring at the bottom of a quartz crucible to achieve the purpose of increasing the contact area of silicon melt and quartz, and the patent (2019101190383) discloses a production process for increasing the oxygen content of a heavy antimony-doped silicon single crystal and production equipment thereof, and also discloses a technology for putting the quartz ring at the bottom of the quartz crucible, but the quartz ring has the defect that the density of quartz is almost the same as that of silicon solution in the quartz crucible, so the quartz ring often floats during specific use, particularly the high temperature and liquid flow are accompanied in the whole crystal pulling process, and the quartz ring floats and moves disorderly under the action of buoyancy force during actual use, so that crystal growth cannot be realized.

SUMMERY OF THE UTILITY MODEL

In order to make up the defects, the utility model provides a quartz ring for improving the oxygen content of heavily antimony-doped silicon single crystal, which solves the problems in the prior art.

The technical scheme of the utility model is that: a quartz ring for improving the oxygen content of heavily antimony-doped silicon single crystal comprises a quartz ring body and is characterized by comprising an anti-floating framework, wherein quartz is fixed on the anti-floating framework, and the quartz wraps the anti-floating framework to form the quartz ring body.

Preferably, a cavity is arranged in the quartz ring body, and copper or molybdenum particles are filled in the cavity to form the anti-floating framework.

Preferably, the anti-floating framework is a hollow circular ring, and the hollow part is filled with copper or molybdenum particles.

Preferably, the width of the ring body at the top of the quartz ring is smaller than that at the bottom, an outer ring wall is formed between the outer edge of the top and the outer edge of the bottom, and the outer ring wall is conical.

Preferably, an inner annular wall is formed between the top inner edge and the bottom inner edge, and the inner annular wall is in an inverted cone shape.

Preferably, the quartz ring body is provided with a solubilization hole, and the solubilization hole penetrates through the quartz ring body.

Above-mentioned structure, when using, owing to increased the anti-frame that floats, the bigger material of cooperation density ratio, for example copper and molybdenum, so has had obvious anti-floating ability, can guarantee that the quartz ring body is in the crucible bottom always when using, the ring body part has adopted trapezium structure, the area of contact of quartz ring body and silicon solution has not only been increased, and the effectual water conservancy diversion of conical surface ability of outer rampart, reduce the influence of the ascending power of fluid, the inner rampart then increases the pressure of cassia silica solution to quartz ring body bottom, the cooperation increases the dissolving hole, the area of contact of quartz ring body and silicon solution has not only been increased, and guaranteed that the quartz ring body is stable arrange the crucible bottom in and not influenced by buoyancy and silicon solution flow.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

Fig. 1 is a first schematic structural diagram of the present invention;

fig. 2 is a schematic structural diagram of the present invention.

Detailed Description

The invention is further described with reference to the following figures and specific examples.

Referring to fig. 1-2, the utility model relates to an improve quartz ring of heavily doping antimony silicon single crystal oxygen content, including quartz ring body 1, still include anti-floating skeleton 2, fixed quartz on anti-floating skeleton 2, quartz parcel anti-floating skeleton framework 2 becomes quartz ring body 1, anti-floating skeleton 2 be a hollow ring, the hollow portion is filled with copper or molybdenum granule, adopt this structure in this embodiment, of course the quartz ring body sets up to cavity, it is also can to fill copper or molybdenum granule in it, but consider that the quartz body breaks or consumes gradually and can become fragile reason, adopted an annular skeleton, the material of anti-floating skeleton 2, can adopt the arbitrary material that does not have an influence to drawing the brilliant, the ring body width at the top of quartz ring be less than the width of bottom, form the outer rampart wall between top outer fringe and the bottom outer fringe, the outer rampart wall is the toper, forms the inner ring wall between top inner part edge and the bottom inner edge, the inner ring wall is the back taper, be equipped with on the quartz ring body and increase dissolving hole 3, increase dissolving hole 3 and run through quartz ring body 1.

In this embodiment, when growing czochralski silicon, oxygen is transported from the quartz crucible wall to the solid-liquid interface and enters the ingot, and the transportation path is divided into the following four steps:

(1) Dissolution reaction between quartz crucible wall and silicon melt:

SiO ₂ (s)＝Si(l)+2O

(2) The oxygen atoms generated from the quartz crucible wall are uniformly distributed in the silicon melt under the stirring action of natural convection.

(3) The oxygen atoms transported to the surface of the silicon melt by convection are volatilized as SiO. Since the vapor pressure of SiO is very low at the melting point temperature of silicon, more than 99% of the oxygen is volatilized.

Si(l)+O＝SiO(g)

(4) Oxygen atoms in the boundary layer are diffused at the front end of the solid-liquid interface, and enter the ingot due to the segregation phenomenon.

Therefore, the contact area of the silicon melt and the quartz is the primary factor affecting the oxygen content, and the larger the contact area, the more the quartz melts, the more oxygen enters the silicon melt. And once the quartz ring is flushed or floated by the fluid, the oxygen increasing effect is basically lost.

The basic principles, main features and advantages of the present invention have been shown and described above. It will be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that the foregoing embodiments and descriptions are provided only to illustrate the principles of the present invention without departing from the spirit and scope of the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A quartz ring for improving the oxygen content of heavily antimony-doped silicon single crystal comprises a quartz ring body and is characterized in that: the quartz ring comprises an anti-floating framework, wherein quartz is fixed on the anti-floating framework, and the quartz wraps the anti-floating framework to form a quartz ring body.

2. The quartz ring for increasing the oxygen content of a heavily antimony-doped silicon single crystal according to claim 1, wherein: a cavity is arranged in the quartz ring body, and copper or molybdenum particles are filled in the cavity to form the anti-floating framework.

3. The quartz ring for increasing the oxygen content of the heavily antimony-doped silicon single crystal according to claim 1, wherein: the anti-floating framework is a hollow circular ring, and copper or molybdenum particles are filled in the hollow part.

4. The quartz ring for increasing the oxygen content of heavily antimony-doped silicon single crystal according to claim 1, 2 or 3, wherein: the width of the ring body at the top of the quartz ring is smaller than that at the bottom, an outer ring wall is formed between the outer edge of the top and the outer edge of the bottom, and the outer ring wall is conical.

5. The quartz ring for increasing the oxygen content of a heavily antimony-doped silicon single crystal according to claim 4, wherein: an inner ring wall is formed between the top inner edge and the bottom inner edge, and the inner ring wall is in an inverted cone shape.

6. The quartz ring for increasing the oxygen content of the heavily antimony-doped silicon single crystal according to claim 1, wherein: and the quartz ring body is provided with a solubilization hole which penetrates through the quartz ring body.