Silicon carbide box convenient for nitrogen purging
By designing X-shaped air inlet and outlet openings and small protrusion structures on the silicon carbide box, rapid nitrogen purging was achieved, oxygen concentration was reduced, wafer processing quality was improved, and the problem of wafer-to-base adhesion was solved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2026-03-24
AI Technical Summary
The existing silicon carbide boxes lack ventilation openings, making it difficult for oxygen to dissipate, which affects the processing quality of the wafers and prevents impurities from entering the heating area.
The design incorporates upper and lower annular protrusions with inlet and outlet openings, forming an X-shaped distribution. Small protrusions and annular guide walls are also provided on the base to ensure that nitrogen can be quickly purged and oxygen discharged, while preventing the wafer from sticking to the base.
It enables rapid nitrogen purging of the wafer heating area, reduces oxygen concentration, improves processing quality, and solves the problem of wafers being difficult to separate from the silicon carbide substrate.
Smart Images
Figure CN224037790U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a silicon carbide box convenient for nitrogen purging belongs to the semiconductor technical field. BACKGROUND
[0002] The wafer is generally stored in the black silicon carbide box when heating, and the heat is conducted to the wafer by heating the black box body. Before heating, nitrogen needs to be purged around the wafer to reduce the oxygen concentration around the wafer, improve the processing quality of the wafer, and prevent impurities from entering the heating area. However, the existing silicon carbide box does not have a gas outlet, and the closed box is difficult to dissipate oxygen in the box, affecting the processing quality of the wafer. SUMMARY
[0003] The utility model aims at the deficiency of prior art, provides a silicon carbide box convenient for nitrogen purging, which can dissipate oxygen in the box by purging nitrogen, reduce the oxygen concentration in the wafer heating area, and improve the processing quality of the wafer.
[0004] The technical scheme of the utility model is as follows:
[0005] A silicon carbide box convenient for nitrogen purging, characterized by comprising an upper cover and a base, the upper cover is provided with an upper circular groove and an upper annular boss, the base is provided with a lower circular groove and a lower annular boss, and the upper and lower annular bosses are arranged around the corresponding circular grooves respectively; two gas inlet slits, two gas outlet slits and two side gas outlet slits are arranged at the corresponding positions of the upper and lower annular bosses, and the two gas inlet slits and the two gas outlet slits are distributed in the shape of X.
[0006] In the above scheme, when the upper cover and the base are closed, the upper and lower annular bosses are attached, and the upper and lower circular grooves form a wafer heating cavity. The 6-inch wafer is placed in the heating cavity. The two gas inlet slits and the two gas outlet slits are arranged opposite to each other and cross-distributed in the shape of X, which helps the nitrogen to quickly enter the silicon carbide box and quickly dissipate the oxygen in the box; the two side gas outlet slits are symmetrically distributed to assist the gas in the box to dissipate. The above scheme can realize the nitrogen purging of the wafer heating area, reduce the oxygen concentration in the heating area, improve the processing quality of the wafer, and prevent impurities from entering the heating area.
[0007] Further, the included angle between the two gas inlet slits is 20°, and the included angle between the two gas outlet slits is 20°. Such arrangement accelerates the flow rate of nitrogen purging in the box, quickly dissipates the oxygen in the box, and improves the effect of nitrogen purging.
[0008] Further, the lower circular groove is provided with a plurality of small bosses in cross shape and uniformly distributed, the height of the small bosses is 0.02mm. Since the surface of the lower circular groove of the silicon carbide box base is very smooth, the surface of the wafer is also very smooth, after the wafer is placed on the silicon carbide box base, it is difficult to separate and take out. The lower circular groove of the silicon carbide box base is processed with some small bosses of 0.02mm, which can prevent the wafer from being bonded when placed in the box, and is difficult to separate, solving the problem that the wafer is difficult to separate from the silicon carbide base.
[0009] Further, all the notches on the upper annular boss or the lower annular boss are at the same height, and the notches are higher than the corresponding circular grooves, and the distance between the notches and the corresponding circular grooves is less than the thickness of the wafer. In this way, after the nitrogen gas enters from the gas inlet notch, it is ensured that the nitrogen gas flows through the upper surface and the lower surface of the wafer, and the oxygen in the box is dispersed, further reducing the oxygen concentration on the upper and lower surfaces of the wafer, and improving the processing quality of the wafer.
[0010] Further, the groove depth of the upper and lower circular grooves is greater than the thickness of the wafer, and the diameter of the upper and lower circular grooves is greater than the diameter of the wafer, so that the wafer heating cavity size between the upper cover and the base is greater than the wafer, facilitating the placement of the wafer, which is not only the heating cavity of the wafer, but also the gas flow cavity for nitrogen blowing, facilitating the discharge of oxygen in the box.
[0011] Further, the lower annular boss of the base is provided with a ring-shaped guide wall at the edge, the inner side of the ring-shaped guide wall is arranged obliquely, so that the ring-shaped guide wall forms a horn shape from large to small, which is beneficial to the cover of the base. The inclination angle of the inner side of the ring-shaped guide wall is 66°, and the minimum inner diameter matches the outer diameter of the upper cover, which can ensure that the upper cover is smoothly covered on the base, and also can ensure that the upper cover is attached to the base.
[0012] Further, the inner side of the ring-shaped guide wall and the edge of the upper cover form a ring-shaped air flow groove, which facilitates the diffusion of excess gas flow at the gas inlet notch, prevents stress concentration, and avoids the separation of the upper cover and the base due to the influence of the gas flow.
[0013] The utility model discloses simple and reasonable structure, low in cost, through simple improvement, increased gas inlet, outlet channel, realize the nitrogen blowing of wafer heating area, reduce the oxygen concentration of heating area, improve the processing quality of wafer, through the increase of a plurality of uniformly distributed small bosses, the problem that wafer is difficult to separate from silicon carbide base is solved. ACCURACY OF DRAWINGS
[0014] Figure 1 It is the top view of the silicon carbide box of the utility model;
[0015] Figure 2 It is Figure 1A-A direction section view;
[0016] Figure 3 For Figure 2 B part enlarged view;
[0017] Figure 4 For the explosion of the silicon carbide box of the utility model;
[0018] Figure 5 For the explosion of the silicon carbide box of the utility model;
[0019] Figure 6 For the schematic diagram of the upper cover of the silicon carbide box of the utility model;
[0020] Figure 7 For the schematic diagram of the base of the silicon carbide box of the utility model (including wafer);
[0021] Figure 8 For the schematic diagram of the base of the silicon carbide box of the utility model;
[0022] Figure 9 For Figure 8 C part enlarged view;
[0023] In the figure: upper cover 1, base 2, upper circular groove 3, upper annular boss 4, lower circular groove 5, lower annular boss 6, air inlet gap 7, air outlet gap 8, side air outlet gap 9, small boss 10, annular guide wall 11, annular air flow groove 12, wafer 13. DETAILED DESCRIPTION
[0024] A kind of silicon carbide box of nitrogen blowing is facilitated, as Figure 1 、 Figure 4 、 Figure 5 As shown, including upper cover 1 and base 2. As Figure 6 As shown, upper cover 1 is equipped with upper circular groove 3, upper annular boss 4, upper circular groove is arranged around. As Figure 8 As shown, base 2 is equipped with lower circular groove 5, lower annular boss 6, lower annular boss is arranged around lower circular groove;Upper cover, base cover is closed, upper, lower annular boss is pasted, upper, lower circular groove forms wafer heating cavity, for placing 6 inch wafer. The depth of upper, lower circular groove is all greater than the thickness of wafer, and the diameter of upper, lower circular groove is all greater than the diameter of wafer, facilitate the wafer to be put in.
[0025] As Figure 6 、 Figure 7 、 Figure 8 As shown, the corresponding place of upper, lower annular boss is equipped with two air inlet gaps 7, two air outlet gaps 8 and two side air outlet gaps 9 respectively, two air inlet gaps, two air outlet gaps are distributed to form X shape, facilitate nitrogen blowing, oxygen discharge in box.
[0026] In one embodiment of the utility model, the included angle between the two gas inlet openings is 20°, the included angle between the two gas outlet openings is 20°, and the gas flow rate is improved.
[0027] In one embodiment of the utility model, a plurality of small bosses 10 in cross shape and uniformly distributed are arranged in the lower circular groove, the height of the small bosses is 0.02mm, and the wafer is prevented from being adsorbed to the base.
[0028] In one embodiment of the utility model, as shown in Figure 8 , Figure 9 , all the openings on the upper annular boss or the lower annular boss are at the same height, the openings are higher than the corresponding circular grooves, the distance between the openings and the corresponding circular grooves is less than the thickness of the wafer, and the wafer is conveniently purged by nitrogen on the upper and lower surfaces.
[0029] In one embodiment of the utility model, as shown in Figure 2 , Figure 3 , the lower annular boss of the base is provided with a ring-shaped guide wall 11 at the edge, the inner side of the ring-shaped guide wall is arranged to be inclined, so that the ring-shaped guide wall forms a horn shape with the upper part being larger and the lower part being smaller, the inclination angle of the inner side of the ring-shaped guide wall is 66°, and the minimum inner diameter of the ring-shaped guide wall is matched with the outer diameter of the upper cover, so that the upper cover is smoothly covered on the base, and the upper cover is also ensured to be attached to the base.
[0030] In one embodiment of the utility model, the inner side of the ring-shaped guide wall 11 and the edge of the upper cover form a ring-shaped air flow groove 12, and the ring-shaped air flow groove is convenient for diffusion of the excess air flow at the gas inlet opening.
Claims
1. A silicon carbide box that is easy to purge with nitrogen, characterized in that, The device includes an upper cover and a base. The upper cover has an upper circular groove and an upper annular protrusion, and the base has a lower circular groove and a lower annular protrusion. The upper and lower annular protrusions are arranged around the corresponding circular grooves. The upper and lower annular protrusions are respectively provided with two air inlets, two air outlets, and two side air outlets at corresponding positions. The two air inlets and two air outlets are distributed in an X-shape.
2. The silicon carbide box that is easy to purge with nitrogen according to claim 1, characterized in that, The lower circular groove is provided with several small protrusions arranged in a cross shape, and the height of the small protrusions is 0.02mm.
3. The silicon carbide box facilitating nitrogen purging according to claim 1, characterized in that, All notches on the upper or lower annular boss are at the same height, and the notches are higher than the corresponding circular grooves.
4. A silicon carbide box that is easy to purge with nitrogen according to claim 3, characterized in that, The distance between the notch and the corresponding circular groove is less than the thickness of the wafer.
5. A silicon carbide box that is easy to purge with nitrogen according to claim 4, characterized in that, The depth of both the upper and lower circular grooves is greater than the thickness of the wafer, and the diameter of both the upper and lower circular grooves is greater than the diameter of the wafer.
6. A silicon carbide box that is easy to purge with nitrogen according to claim 1, characterized in that, The lower annular boss of the base has an annular guide wall at its edge; the inner side of the annular guide wall is arranged at an angle, so that the annular guide wall forms a trumpet shape that is larger at the top and smaller at the bottom.
7. A silicon carbide box that is easy to purge with nitrogen according to claim 6, characterized in that, The annular guide wall has an inclination angle of 66° on its inner side, and its minimum inner diameter matches the outer diameter of the top cover.
8. A silicon carbide box that is easy to purge with nitrogen according to claim 7, characterized in that, An annular airflow groove is formed between the inner side of the annular guide wall and the edge of the top cover.