Inductively Coupled Plasma Device and Semiconductor Thin Film Equipment

Abstract

The present invention discloses an inductively coupled plasma device and a semiconductor thin film device. The inductively coupled plasma device includes: a plasma device body, an isolation cover plate, an antenna, and a shielding member; wherein, the isolation cover plate is covered on the plasma device body to form a vacuum chamber, the antenna is arranged above the isolation cover plate, and the shielding member is arranged on the isolation cover plate and is between the isolation cover plate and the antenna; the antenna includes a plurality of sub-antennas arranged side by side, and the plurality of sub-antennas are connected in parallel; the shielding member includes a first member with a straight strip structure and a plurality of second members, the plurality of second members are arranged at intervals along the length direction of the first member and are vertically intersecting the first member. The present invention solves the problem of poor plasma uniformity in the chamber of the inductively coupled plasma device by arranging a plurality of sub-antennas side by side and arranging a shielding member between the sub-antennas and the isolation cover plate.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technologies, and particularly to an inductively coupled plasma device and a semiconductor thin film device. Background Art

[0002] An inductively coupled plasma (ICP) chamber is a common device in plasma processes for microelectronics manufacturing. In such a device, the radio frequency magnetic field in a low-pressure reaction chamber is generated by the radio frequency energy transmitted by a planar antenna through a dielectric window into the chamber by inducing the radio frequency oscillating current. This magnetic field generates a circulating electron flow in the process gas introduced into the chamber, generating a plasma composed of ions, free electrons, neutral substances, and free radicals. The energy coupling efficiency, that is, the amount of energy transferred from the antenna to the plasma, is an important factor in the ICP device. There are usually two coupling modes in the ICP source device: capacitive coupling mode (E mode) and inductive mode (H mode). Among them, the coupling efficiency of the capacitive coupling mode is relatively low, which is what is desired to be minimized as much as possible in the ICP device. In the initial stage of plasma generation by the ICP device, a low-density plasma is generated by the E mode. When the plasma density reaches a certain value, an E-H mode conversion occurs, and a higher-density plasma is mainly generated by discharging in the H mode.

[0003] During the process of generating plasma by the above ICP device, there are different load impedances in the plasma E mode and H mode. The matching network needs to be adjusted in a timely manner to ensure impedance matching between the RF power supply and the load. When the two modes are converted during plasma generation, it will cause plasma instability and cause impedance changes in the plasma. And the rapid change in the impedance of the plasma will affect the energy coupling efficiency of the antenna, which in turn will change the impedance of the plasma. This will form a low-amplitude impedance oscillation, resulting in the matching network being unable to reach a stable matching state, and it is also difficult for the plasma to reach a stable state. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an inductively coupled plasma device and a semiconductor thin film device to solve the problem of poor plasma uniformity in the chamber of the inductively coupled plasma device.

[0005] To solve the above technical problem, according to one aspect of the present invention, there is provided an inductively coupled plasma device, including: a plasma device body, an isolation cover plate, an antenna, and a shielding member;

[0006] Wherein, the isolation cover plate is covered on the plasma device body to form a vacuum chamber, the antenna is arranged above the isolation cover plate, and the shielding member is arranged on the isolation cover plate and is between the isolation cover plate and the antenna;

[0007] The antenna includes a plurality of sub-antennas arranged side by side, and the plurality of sub-antennas are connected in parallel;

[0008] The shielding member includes a first member having a straight bar structure and a plurality of second members. The plurality of second members are arranged at intervals along the length direction of the first member and intersect perpendicularly to the first member.

[0009] In some embodiments, the plurality of sub-antennas have a planar single spiral structure. Every two sub-antennas are divided into a group, and the winding directions of the two sub-antennas in each group are opposite.

[0010] In some embodiments, the sub-antenna is formed by winding a hollow metal tube.

[0011] In some embodiments, a cooling substance is disposed inside the metal tube to cool the sub-antenna.

[0012] In some embodiments, the straight bar structure with the largest length among the first member and the plurality of second members is parallel to the arrangement direction of the plurality of sub-antennas.

[0013] In some embodiments, the plurality of second members are symmetrically arranged with the first member and / or the second member at the center of the first member as the center line.

[0014] In some embodiments, along the direction from the center of the first member towards both ends, the lengths of the plurality of second members gradually decrease.

[0015] In some embodiments, along the direction from the center of the first member towards both ends, the lengths of the plurality of second members gradually increase.

[0016] In some embodiments, a heating element and / or a grounding element is disposed on the shielding member.

[0017] According to another aspect of the present invention, there is provided a semiconductor thin film device including the inductively coupled plasma device described in any one of the above embodiments.

[0018] Compared with the prior art, the present invention has obvious advantages and beneficial effects. By means of the above technical solutions, an inductively coupled plasma device and a semiconductor thin film device of the present invention can achieve considerable technical progressiveness and practicality, and have wide industrial utilization value. It has at least the following advantages:

[0019] (1) The antenna of the inductively coupled plasma device of the present invention is set as a plurality of sub-antennas arranged side by side, which can form a large-range uniform plasma in the vacuum chamber of the inductively coupled plasma device to meet the usage requirements of large-sized substrates. By arranging the plurality of sub-antennas in parallel, the inductance generated by the antenna can be reduced, and the energy coupling efficiency can be improved during the generation of the plasma.

[0020] (2) By arranging a shielding member between the isolation cover plate and the antenna, the present invention can effectively adjust the uniformity of the radial distribution of the plasma and expand the region with uniform radial distribution.

[0021] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the content of the specification. And in order to make the above and other objects, features, and advantages of the present invention more obvious and understandable, the following specifically gives preferred embodiments and, in conjunction with the accompanying drawings, details are described as follows. Brief Description of the Drawings

[0022] Figure 1 Shows a schematic structural diagram of an inductively coupled plasma device according to an embodiment of the present invention;

[0023] Figure 2 Shows a schematic structural diagram of an antenna according to an embodiment of the present invention;

[0024] Figure 3 Shows a schematic structural diagram of a shielding member according to an embodiment of the present invention;

[0025] Figure 4 Shows a schematic structural diagram of a shielding member according to another embodiment of the present invention.

[0026]

Symbol Description

[0027] 1: Radio frequency power supply

[0028] 2: Impedance matching network

[0029] 3: Antenna

[0030] 31: Sub-antenna

[0031] 4: Plasma device body

[0032] 5: Isolation cover plate

[0033] 6: Vacuum chamber

[0034] 7: Wafer

[0035] 8: Carrier stage

[0036] 9: Injection hole

[0037] 10: Air pump interface

[0038] 11: Shielding component

[0039] 111: First component

[0040] 112: Second component Detailed implementation manners

[0041] To further elaborate the present invention, the following will, in conjunction with the accompanying drawings, provide a detailed description of the specific implementation manners of an inductively coupled plasma device and a semiconductor thin film device according to the present invention.

[0042] As Figure 1 shown, the inductively coupled plasma device includes a radio frequency power supply 1, an impedance matching network 2 (impedance matching network), an antenna 3 (antenna), a plasma device body 4, and an isolation cover plate 5. The radio frequency power supply 1, the impedance matching network 2, and the antenna 3 are connected in sequence, and an electromagnetic field is generated in the vacuum chamber 6 surrounded by the plasma device body 4 and the isolation cover plate 5, and then the gas in the vacuum chamber 6 generates plasma through electromagnetic induction.

[0043] In the inductively coupled plasma device, the antenna 3 is placed close to the isolation cover plate 5 of the vacuum chamber 6 and is connected to the radio frequency power supply 1 and the impedance matching network 2. The radio frequency power supply 1 maximizes the power delivered to the antenna 3 by adjusting the impedance matching network 2. The radio frequency current (RF current) loaded into the antenna 3 generates a radio frequency electromagnetic field around the antenna 3 and penetrates the isolation cover plate 5 (dielectric) to reach the vacuum chamber 6. The gas in the vacuum chamber 6 will be ionized in the radio frequency electromagnetic field to form plasma, so as to process the wafer 7 (placed on the stage 8). The process gas is injected into the vacuum chamber 6 through the injection hole 9 and is exported from the vacuum chamber 6 through the chamber air pump interface 10, and a negative pressure will be formed in the vacuum chamber 6.

[0044] An embodiment of the present invention provides an inductively coupled plasma device, as Figure 1 shown, including a plasma device body 4, an isolation cover plate 5, an antenna 3, and a shielding component 11.

[0045] Among them, the isolation cover plate 5 is covered on the plasma device body 4 to enclose and form a vacuum chamber 6. The antenna 3 is arranged above the isolation cover plate 5 to generate a radio frequency electromagnetic field in the vacuum chamber 6. The shielding component 11 is arranged on the isolation cover plate 5 and is located between the isolation cover plate 5 and the antenna 3.

[0046] Specifically, the shielding component 11 is a Faraday shield, and the radio frequency electromagnetic field generated by the antenna 3 is controlled by the shielding component 11 to control the magnetic field strength in different regions of the vacuum chamber 6, so as to adjust the magnetic field uniformity in the radial direction of the vacuum chamber 6.

[0047] In one embodiment, as Figure 2 shown, the antenna 3 includes a plurality of sub-antennas 31 arranged side by side, and the plurality of sub-antennas 31 are connected in parallel to the impedance matching network 2 of the inductively coupled plasma device.

[0048] In the present invention, the antenna 3 is formed by arranging a plurality of sub-antennas 31 side by side, and a large-range uniform plasma can be formed in the vacuum chamber 6 of the inductively coupled plasma device to meet the usage requirements of large-size substrates. By arranging the plurality of sub-antennas 31 in parallel, the inductance generated by the antenna 3 can be reduced, and the energy coupling efficiency can be improved during the plasma generation process.

[0049] Specifically, as Figure 2 shown, the plurality of sub-antennas 31 are of a planar single spiral structure, and every two sub-antennas 31 are divided into a group. The winding directions of the two sub-antennas 31 in each group are opposite. That is to say, in the two sub-antennas 31 of each group, the winding direction of one sub-antenna 31 is clockwise, and the winding direction of the other sub-antenna 31 is counterclockwise.

[0050] Preferably, the antenna 3 includes four sub-antennas 31, and the four antennas 3 are divided into two groups, and each group includes two sub-antennas 31. Of course, the antenna 3 may also include six, eight, etc. sub-antennas 31, and the present invention does not limit the number of sub-antennas 31.

[0051] The antenna 3 can be wound with a solid metal wire or a hollow metal tube.

[0052] Furthermore, when the antenna 3 is wound with a hollow metal tube, a cooling substance can be introduced into the metal tube to cool the antenna 3. The cooling substance can be a liquid or gas with low conductivity, and the present invention is not limited thereto.

[0053] As Figure 3 and Figure 4 shown, the shielding member 11 includes a first member 111 with a straight bar structure and a plurality of second members 112 with a straight bar structure. The plurality of second members 112 are arranged at intervals along the length direction of the first member 111 and are vertically intersecting with the first member 111.

[0054] In this embodiment, the plurality of second members 112 may be evenly spaced, that is, the distance between every two adjacent second members 112 is the same. Of course, the plurality of second members 112 may also be arranged in a non-uniform spacing manner. For example, taking the second member 112 on the center line of the first member 111 as the demarcation line, the distance between the remaining second members 112 on both sides of this second member 112 is the same, but the distance between the second member 112 on the center line of the first member 111 and its adjacent second member 112 is different from the distance between other adjacent second members 112.

[0055] Of course, whether the plurality of second members 112 are evenly spaced can be adjusted according to the style and layout of the antenna 3, and the present invention is not limited to whether the plurality of second members 112 are evenly spaced.

[0056] In one embodiment, the longest straight bar structure in the first member 111 and the plurality of second members 112 is parallel to the arrangement direction of the plurality of sub-antennas 31.

[0057] Specifically, when the longest straight bar structure in the first member 111 and the plurality of second members 112 is the first member 111, then the first member 111 is parallel to the arrangement direction of the plurality of sub-antennas 31; when the longest straight bar structure in the first member 111 and the plurality of second members 112 is one of the second members 112, then the longest second member 112 is parallel to the arrangement direction of the plurality of sub-antennas 31.

[0058] In one embodiment, the plurality of second members 112 are symmetrically arranged with the first member 111 as the center line, that is, the length of each second member 112 on both sides of the first member 111 is the same.

[0059] In another embodiment, the plurality of second members 112 are symmetrically arranged with the second member 112 at the center of the first member 111 as the center line. That is, among the plurality of second members 112, when the distances of every two second members from the second member 112 at the center of the first member 111 are the same, then the lengths of these two members are the same.

[0060] In another embodiment, as Figure 3 and Figure 4 shown, while the plurality of second members 112 are symmetrically arranged with the first member 111 as the center line, they are also symmetrically arranged with the second member 112 at the center of the first member 111 as the center line. That is, not only is the length of each second member 112 on both sides of the first member 111 the same, but also among the plurality of second members 112, when the distances of every two second members from the second member 112 at the center of the first member 111 are the same, then the lengths of these two members are also the same.

[0061] Furthermore, the lengths of the plurality of second members 112 are different. Specifically, in the direction from the center of the first member 111 towards both ends of the first member 111, the lengths of the second members 112 change successively.

[0062] In one embodiment, as Figure 3 shown, in the direction from the center of the first member 111 towards both ends of the first member 111, the lengths of the second members 112 decrease successively. That is, among the plurality of second members 112, the length of the second member 112 at the center of the first member 111 is the largest, and in the direction towards both ends of the first member 111, the lengths of the second members 112 decrease successively.

[0063] In another embodiment, as Figure 4 shown, in the direction from the center of the first member 111 towards both ends of the first member 111, the lengths of the second members 112 increase successively. That is, among the plurality of second members 112, the length of the second member 112 at the center of the first member 111 is the smallest, and in the direction towards both ends of the first member 111, the lengths of the second members 112 increase successively.

[0064] In one embodiment, a heating element (not shown in the figure) is provided on the shielding member 11 to heat the shielding member 11.

[0065] In one embodiment, a grounding element is provided on the shielding member 11 to ground the shielding member 11 through the grounding element, so as to reduce the parasitic capacitance of the shielding member 11, reduce the capacitive coupling part that generates plasma, reduce the amplitude of impedance oscillation, and further improve the stability of the plasma.

[0066] An embodiment of the present invention further provides a semiconductor thin film device, including the inductively coupled plasma device of any one of the above embodiments.

[0067] The above are only preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An inductively coupled plasma device, characterized in that, Comprising: A plasma device body, an isolation cover plate, an antenna, and a shielding member; Wherein, the isolation cover plate is disposed on the plasma device body to form a vacuum chamber, the antenna is disposed above the isolation cover plate, and the shielding member is disposed on the isolation cover plate and is between the isolation cover plate and the antenna; The antenna includes a plurality of sub-antennas arranged side by side, and the plurality of sub-antennas are connected in parallel; The shielding member includes a first member having a straight strip structure and a plurality of second members, and the plurality of second members are spaced apart along the length direction of the first member and intersect the first member perpendicularly; At least some of the lengths between the first member and the plurality of second members and between the plurality of second members are different, and the longest one of the first member or the plurality of second members is parallel to the arrangement direction of the plurality of sub-antennas; The plurality of second members are symmetrically arranged with the first member and / or the second member at the center of the first member as the center line.

2. The inductively coupled plasma device according to claim 1, wherein The plurality of sub-antennas are of a planar single spiral structure, and every two sub-antennas are divided into a group, and the winding directions of the two sub-antennas in each group are opposite.

3. The inductively coupled plasma device according to claim 1 or 2, characterized in that, The sub-antenna is wound by a hollow metal tube.

4. The inductively coupled plasma device according to claim 3, wherein A cooling substance is disposed in the metal tube to cool the sub-antenna.

5. The inductively coupled plasma device according to claim 1, wherein Along the direction from the center of the first member towards both ends, the lengths of the plurality of second members decrease in sequence.

6. The inductively coupled plasma device according to claim 1, characterized in that, Along the direction from the center of the first member towards both ends, the lengths of the plurality of second members increase in sequence.

7. The inductively coupled plasma device according to claim 1 or 2, characterized in that A heating element and / or a grounding element is disposed on the shielding member.

8. A semiconductor thin film device, characterized in that, Comprising the inductively coupled plasma device according to any one of claims 1-7.

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