Plasma thin film deposition equipment with central air exhaust function

Abstract

The invention relates to plasma thin film deposition equipment with central air exhaust. The plasma thin film deposition equipment comprises a reaction chamber, a heating stage, a heating stage base, a lifter, an air exhaust device, a first elastic pipeline and a second elastic pipeline, the heating table is divided into a bearing part and a supporting part vertically arranged in the middle of the bottom surface of the bearing part; a first gap is formed between the bearing part and the inner side of the reaction chamber; the bottom end of the supporting part extends out of the bottom of the reaction chamber and is fixedly connected with the heating stage base; a second gap is formed between the supporting part and the bottom of the reaction chamber; the lifter drives the heating stage base to do lifting motion in the direction perpendicular to the bearing part so as to drive the bearing part to do lifting motion; the first elastic pipeline is sleeved outside the extending part of the bearing part and is fixedly connected between the bottom of the reaction chamber and the heating stage base in a sealing manner, and the top surface of the heating stage base is fixedly connected with the air extractor through the second elastic pipeline; the heating stage base is provided with more than one through hole, and the through hole is communicated with the first elastic pipeline and the second elastic pipeline to form an air exhaust channel. The problem of edge deviation effect is effectively solved, and the thickness of the thin film is uniform.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical vapor deposition, and in particular, to a plasma thin film deposition device with central air extraction. Background Art

[0002] Chemical Vapor Deposition (CVD) technology is the main technology used to prepare high-purity and high-performance solid thin films. A typical CVD process is a method of introducing one or more vapor source atoms or molecules into a chamber, where a chemical reaction occurs under the action of external energy and a desired thin film is formed on the surface of a wafer. Due to the advantages of a wide film formation range and good reproducibility of CVD technology, it is widely used for various film formations in different forms.

[0003] As Figure 1 shown, in the existing plasma thin film deposition device, the air inlet is arranged above the center of the hot stage, and the top of the hot stage serves as a carrier stage for the wafer and also has a heating function. Its reaction chamber generally uses single-sided air extraction, that is, the air extraction port is arranged on the side of the hot stage, which will cause the edge effect to occur. As Figure 2 shown, the edge effect refers to the phenomenon that the gas flow dynamics and heat distribution at the edge of the thin film are different from those in the central region, resulting in non-uniform deposition rate and thin film quality. The uniformity of the thin film deposition thickness is an important index for measuring the thin film quality. Summary of the Invention

[0004] In view of this, the present invention provides a plasma thin film deposition device with central air extraction, which makes the gas distribution in the reaction chamber more uniform, effectively solves the edge effect problem, and makes the film thickness more uniform.

[0005] The present invention is realized through the following technical solutions: A plasma thin film deposition device with central air extraction, comprising a reaction chamber, a hot stage, a hot stage base, a lift, an air extraction device, a first elastic pipeline, and a second elastic pipeline; the hot stage is divided into a bearing part and a supporting part vertically arranged in the middle of the bottom surface of the bearing part from top to bottom; the bearing part is suspended and embedded in the reaction chamber, and the bearing part is used for carrying wafers, and there is a first gap between the bearing part and the inner side of the reaction chamber; the bottom end of the supporting part extends out of the bottom of the reaction chamber and is fixedly connected to the hot stage base, and there is a second gap between the supporting part and the bottom of the reaction chamber; an air inlet is arranged at the top of the reaction chamber, and the air inlet faces the middle of the bearing part; the hot stage base is fixedly connected to the lift, and the lift drives the hot stage base to move up and down in a direction perpendicular to the bearing part, thereby driving the bearing part to move up and down; the first elastic pipeline is sleeved outside the extending part of the bearing part and is hermetically fixedly connected between the bottom of the reaction chamber and the hot stage base, and the top surface of the hot stage base is fixedly connected to the air extraction device through the second elastic pipeline; the hot stage base is provided with more than one through hole, and the through hole communicates the first elastic pipeline and the second elastic pipeline; the first gap, the second gap, the first elastic pipeline, the through hole, and the second elastic pipeline form an air extraction channel.

[0006] Further, the hot stage base moves up and down, driving the first elastic pipeline and the second elastic pipeline to perform telescopic movement in the up and down direction, and the total length of the first elastic pipeline and the second elastic pipeline remains unchanged.

[0007] Further, the bottom end of the extending part of the supporting part is fixedly connected to the middle of the hot stage base, and the hot stage base is provided with a wire passing hole, and the wire passing hole is used for leading out the hot stage cable; the wire passing hole is not communicated with the first elastic pipeline and the second elastic pipeline.

[0008] Further, several through holes are uniformly arranged around the middle of the hot stage; the wire passing hole is arranged between any two through holes.

[0009] Further, the supporting part, the first elastic pipeline, the second elastic pipeline, and the hot stage base are coaxial.

[0010] Further, both the first elastic pipeline and the second elastic pipeline adopt metal bellows.

[0011] Compared with the existing technology, the beneficial effects of the present invention are: 1. In the present invention, the supporting part is vertically arranged in the middle of the hot stage bearing part, the first elastic pipeline is sleeved outside the extending part of the hot stage, and is communicated with the second elastic pipeline through the through hole of the hot stage base. The first gap and the second gap enable the gas to be evenly extracted from the middle of the bearing part, avoiding the edge effect caused by side air extraction in the prior art, making the gas distribution in the reaction chamber uniform, and thus the film thickness is more uniform.

[0012] 2. The present invention adopts an upper and lower double elastic sealing pipeline design and integrates a lifting function, so that during the entire deposition reaction process, while the hot stage moves up and down, the length of the air extraction channel remains unchanged, ensuring that the air extraction rate remains unchanged and further ensuring the uniformity of the thin film.

[0013] 3. The wire threading hole of the present invention only communicates the middle part and the periphery of the hot stage base, and the wire threading hole is not communicated with the through hole, and the wire threading hole is not communicated with the first elastic pipeline and the second elastic pipeline, so as to ensure the airtightness of the entire air extraction channel while leading out the hot stage cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of an existing deposition device.

[0015] Figure 2 It is a gas distribution diagram of the reaction chamber of an existing deposition device.

[0016] Figure 3 It is a schematic structural diagram of the present invention.

[0017] Figure 4 It is a working principle diagram of the present invention.

[0018] Figure 5 It is a gas distribution diagram of the deposition reaction chamber of the present invention.

[0019] Figure 6 It is a schematic diagram of the connection between the corrugated pipe and the lifting seat of the present invention.

[0020] Figure 7 It is an axonometric view of the lifting seat of the present invention.

[0021] Among them, 1 - reaction chamber, 2 - upper cavity, 3 - hot stage, 3-1 - bearing part, 3-2 - supporting part, 4 - first elastic pipeline, 5 - hot stage cable, 6 - elevator, 7 - second elastic pipeline, 8 - hot stage base, 9 - through hole, 10 - wire threading hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0023] The present invention provides a plasma thin film deposition device with central air extraction, as Figure 3 shown. The deposition device includes a reaction chamber 1, a hot stage 3, a hot stage base 8, an air extraction device, an elevator 6, a first elastic pipeline 4 and a second elastic pipeline 7.

[0024] The hot stage 3 is divided into a bearing part 3-1 and a support part 3-2 from top to bottom. The support part 3-2 is vertically arranged in the middle of the bottom surface of the bearing part 3-1. The bearing part 3-1 is suspended and embedded in the reaction chamber 1, and the bearing part 3-1 is used to carry the wafer. The bottom end of the support part 3-2 extends out of the bottom of the reaction chamber 1, and the bottom end of the support part 3-2 is fixedly connected to the top of the hot stage base 8. The side surface of the hot stage base 8 is fixedly connected to the elevator 6. There is a circumferential first gap between the edge of the bearing part 3-1 and the inner side of the reaction chamber 1, and a circumferential second gap between the edge of the support part 3-2 and the bottom of the reaction chamber 1. Since the support part 3-2 is arranged in the middle of the bottom surface of the bearing part 3-1, the second gap between the support part 3-2 and the bottom of the reaction chamber 1 is also in the middle of the bearing part 3-1.

[0025] An upper cavity 2 is provided at the top of the reaction chamber 1 to seal the reaction chamber 1. The upper cavity 2 is provided with an air inlet, which is located above the bearing part 3-1 and the air inlet faces the middle of the bearing part 3-1. Specifically, during implementation, the wafer is placed in the middle of the upper surface of the bearing part 3-1 to ensure uniform air flow around the wafer.

[0026] The first elastic pipeline 4 is coaxially sleeved outside the protruding part of the support part 3-2, and is hermetically and fixedly connected between the bottom of the reaction chamber 1 and the hot stage base 8. Specifically, the protruding part of the support part 3-2 is arranged inside the first elastic pipeline 4. The top of the first elastic pipeline 4 is hermetically and fixedly connected to the bottom of the reaction chamber 1, and the bottom of the first elastic pipeline 4 is hermetically and fixedly connected to the top of the hot stage base 8.

[0027] The hot stage base 8 is fixedly connected to the pumping device through the second elastic pipeline 7. Specifically, the second elastic pipeline 7 is coaxial with the first elastic pipeline 4. The top of the second elastic pipeline 7 is hermetically and fixedly connected to the bottom of the hot stage base 8, and the bottom of the second elastic pipeline 7 is hermetically and fixedly connected to the pumping device.

[0028] The hot stage base 8 is provided with more than one through hole 9, and the through hole 9 penetrates the top and bottom of the hot stage base 8, that is, the through hole 9 communicates the first elastic pipeline 4 and the second elastic pipeline 7. As Figure 4 shown, the first gap, the second gap, the first elastic pipeline 4, the through hole 9, and the second elastic pipeline 7 form a closed pumping channel. Since the support part 3-2 is arranged in the middle of the bearing part 3-1, when the pumping device works, the gas uniformly converges from the first gap between the bearing part 3-1 and the reaction chamber 1 to the second gap between the middle support part 3-2 and the bottom of the reaction chamber 1, and then is pumped out through the first elastic pipeline 4, the through hole 9, and the second elastic pipeline 7 to realize central pumping. As Figure 5 shown, it ensures uniform gas distribution around the wafer and effectively solves the edge effect.

[0029] The lift 6 drives the hot stage base 8 to move up and down in a direction perpendicular to the carrier table of the carrier part 3-1, so as to drive the carrier part 3-1 to move up and down in the reaction chamber 1 through the support part 3-2, making the chemical vapor deposition reaction more uniform; at the same time, the first elastic pipeline 4 and the second elastic pipeline 7 perform telescopic movement along the lifting direction. Specifically, when the hot stage base 8 moves upward, the first elastic pipeline 4 is compressed accordingly, and the second elastic pipeline 7 is elongated accordingly; when the hot stage base 8 moves downward, the first elastic pipeline 4 is elongated accordingly, and the second elastic pipeline 7 is compressed accordingly; that is, during the lifting movement of the hot stage base 8, the total length of the first elastic pipeline 4 and the second elastic pipeline 7 remains unchanged, ensuring that the length of the air extraction channel remains unchanged, that is, the distance between the air extraction device and the reaction chamber 1 remains unchanged, making the air extraction rate always consistent, and further ensuring the uniformity of the film reaction on the wafer. The first elastic pipeline 4 and the second elastic pipeline 7 can both adopt metal bellows.

[0030] In specific implementation, the bottom end of the extending part of the hot stage 3 is fixedly connected to the groove provided in the middle of the hot stage base 8. A wire passing hole 10 is provided inside the hot stage base 8, and the wire passing hole 10 is used for leading out the hot stage cable 5. In this embodiment, as Figure 6 , 7 shown, a plurality of through holes 9 are evenly arranged around the middle of the hot stage 3; the wire passing hole 10 is arranged between any two through holes 9, the wire passing hole 10 is not communicated with the through holes 9, the axis of the wire passing hole 10 can be perpendicular to the axis of the support part 3-2, one end is communicated with the groove in the middle of the hot stage base 8, and the other end penetrates through the side wall end face of the hot stage base 8, that is, the wire passing hole 10 is not communicated with the first elastic pipeline 4 and the second elastic pipeline 7. The hot stage cable 5 extends from the bottom of the support part 3-2 and is led out from the wire passing hole 10 to the outside of the hot stage base 8. The wire passing hole 10 only communicates the middle and the outside of the hot stage base 8, the wire passing hole 10 is not communicated with the through holes 9, and the wire passing hole 10 is not communicated with the first elastic pipeline 4 and the second elastic pipeline 7, which can ensure the airtightness of the entire air extraction channel while leading out the hot stage cable 5.

[0031] For the plasma thin film deposition equipment provided by the present invention, the air extraction channel is arranged in the middle of the carrier part 3-1. When the air extraction device performs air extraction, the gas is evenly extracted from the middle, avoiding the edge effect caused by side air extraction in the prior art, making the gas distribution in the reaction chamber 1 more uniform and the film thickness more uniform; adopting the upper and lower double elastic sealing pipeline design and integrating and upgrading the function, during the lifting movement of the hot stage 3 in the whole deposition reaction process, the length of the air extraction channel remains unchanged, ensuring that the air extraction rate remains unchanged, and further ensuring the uniformity of the thin film.

[0032] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A centrally-exhausted plasma thin film deposition device, characterized in that: It includes a reaction chamber, a hot stage, a hot stage base, a lifter, a gas extraction device, a first elastic pipeline and a second elastic pipeline; The hot stage is divided into a bearing part and a supporting part vertically arranged in the middle of the bottom surface of the bearing part from top to bottom; the bearing part is suspended and embedded in the reaction chamber, the bearing part is used to bear the wafer, and there is a first gap between the bearing part and the inner side of the reaction chamber; the bottom end of the supporting part extends out of the bottom of the reaction chamber and is fixedly connected to the hot stage base, and there is a second gap between the supporting part and the bottom of the reaction chamber; an air inlet is arranged at the top of the reaction chamber, and the air inlet faces the middle of the bearing part; the hot stage base is fixedly connected to the elevator, and the elevator drives the hot stage base to move up and down in a direction perpendicular to the bearing part, thereby driving the bearing part to move up and down; The first elastic pipeline is sleeved outside the extension of the bearing part and is sealed and fixed between the bottom of the reaction chamber and the hot plate base. The top surface of the hot plate base is fixed to the exhaust device through the second elastic pipeline. The hot plate base is provided with one or more through holes, and the through holes communicate with the first elastic pipeline and the second elastic pipeline. The first gap, the second gap, the first elastic pipeline, the through holes, and the second elastic pipeline constitute an exhaust channel.

2. The centrally-exhausted plasma thin film deposition apparatus according to claim 1, characterized in that: The lifting movement of the heating platform base drives the first elastic pipeline and the second elastic pipeline to perform telescopic movement along the lifting direction, and the total length of the first elastic pipeline and the second elastic pipeline remains unchanged.

3. The centrally-exhausted plasma thin film deposition apparatus according to claim 2, characterized in that: The bottom end of the extension of the support part is fixedly connected to the middle of the heating platform base. The heating platform base is provided with a threading hole, which is used for leading out the heating platform cable; the threading hole is not connected with the first elastic pipeline and the second elastic pipeline.

4. The centrally-exhausted plasma thin film deposition apparatus according to claim 3, characterized in that: A plurality of through holes are evenly arranged around the middle of the heating platform; and the threading hole is arranged between any two through holes.

5. The centrally-exhausted plasma thin film deposition apparatus according to claim 3, characterized in that: The support part, the first elastic pipeline, the second elastic pipeline and the heating platform base are coaxial.

6. The centrally-exhausted plasma thin film deposition device according to any one of claims 1 to 5, characterized in that: The first elastic pipeline and the second elastic pipeline are both made of metal bellows.

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