TWI534890B - Plasma processing device - Google Patents

Description

Plasma processing device

The present invention relates to the field of plasma processing technology, and in particular, to an inductively coupled plasma processing apparatus.

Plasma processing devices are widely used in the manufacturing process of integrated circuits, such as deposition, etching, and the like. Among them, the inductively coupled plasma (ICP) device is one of the mainstream technologies in the plasma processing device. The principle is mainly to use the RF power to drive the inductive coupling coil to generate a strong high-frequency alternating magnetic field, so that the low voltage The reaction gas is ionized to produce a plasma. The plasma contains a large number of active particles such as electrons, ions, excited atoms, molecules and radicals. The active particles can undergo various physical and chemical reactions on the surface of the wafer to be processed, and the surface morphology of the wafer changes. That is, the etching process is completed; in addition, the above-mentioned active ions have higher activity than the conventional gaseous reactants, and can promote the chemical reaction between the reaction gases, that is, plasma enhanced chemical vapor deposition (PECVD) can be realized.

According to the requirements of the plasma etching process, the generated plasma usually reaches a certain temperature to perform a better etching process, so a device for heating the plasma is required in the plasma region. In the prior art, a heating element is disposed inside the side wall of the plasma processing apparatus, and temperature control of the plasma in the reaction chamber is realized by the heating element. However, since the sidewall material of the reaction chamber is a good conductor of heat, the heating element When the plasma is heated inside the reaction chamber, the temperature outside the reaction chamber is too high. At the same time, the heat provided by the heating element is conducted upwards and downwards, which not only wastes energy, but also makes the temperature of other components of the reaction chamber uncontrollable, affecting the etching. The process is carried out.

In order to solve the above technical problems, the present invention provides a plasma processing apparatus comprising at least one cavity housing and at least one reaction chamber, wherein a base is provided in the reaction chamber for supporting the substrate, the cavity housing including an insulating window and located a cavity cover under the insulating window, a cavity sidewall disposed under the cavity cover, a plasma heating ring disposed between the cavity cover and the sidewall of the cavity, and a heating element disposed in the plasma heating ring At least one insulated channel is disposed around the heating element.

Preferably, at least two heat insulating channels are disposed around the heating element, the first heat insulating channel is close to a contact surface of the plasma heating ring and the cavity cover, and the second heat insulating channel is adjacent to The contact surface of the plasma heating ring and the sidewall of the cavity, the two heat insulating channels are substantially parallel.

Further, a third insulating channel is disposed around the heating element, and the third insulating channel is substantially perpendicular to the first insulating channel and the second insulating channel.

Preferably, the third heat insulating channel is disposed on a side of the heating element adjacent to an outer space of the reaction chamber.

Preferably, the third insulated channel is in communication with the first two insulated channels.

Preferably, a heat insulating channel is disposed around the heating element, and the heat insulating channel is an arc channel disposed around the heating element, and is disposed on a side of the heating element near the outer space of the reaction cavity.

Preferably, the plasma heating ring is made of aluminum or aluminum alloy.

Preferably, the plasma processing device is an inductively coupled plasma processing device.

Preferably, the plasma heating ring includes an upper end adjacent to the cavity cover and a lower end adjacent to the sidewall of the cavity, the upper end having a radial width greater than the lower end radial width.

Preferably, the lower end of the plasma heating ring and the side wall of the cavity are arranged in parallel with a certain gap therebetween.

The invention has the advantages that: by setting a plasma heating ring with a heating element, the plasma heating in the reaction chamber is realized, and the plasma processing temperature requirement is met; and an insulating channel is arranged around the heating element, The heat generated by the heating element of the plasma heating ring is isolated from the surrounding components and the external space, so that the heat is not lost, and the temperature between the components can be independently controlled, and the reaction process can be temperature-dependent at different positions. Different needs. The insulation channel isolates the heat generated by the heating element from the external space, ensuring that the temperature of the external space does not pose a threat to the operator.

100‧‧‧ cavity shell

101‧‧‧Reaction chamber

105‧‧‧Inductance coil

110‧‧‧Insulated window

120‧‧‧ cavity cover

130‧‧‧Plastic heating ring

131, 132, 133‧‧‧ insulated channels

135‧‧‧ heating element

136‧‧‧ upper end

137‧‧‧Bottom

138‧‧‧ gap

140‧‧‧ cavity sidewall

145‧‧‧Import

150‧‧‧Base

170‧‧‧Vacuum pump

200‧‧‧ substrates

Other features, objects, and advantages of the present invention will become apparent from the Detailed Description of Description

The following drawings constitute a part of the specification, and together with the specification, various embodiments are illustrated to explain and clarify the purpose of the invention. The following figures do not depict all of the technical features of the specific embodiments, nor the actual size and true scale of the components.

1 is a schematic structural view of a plasma processing apparatus according to the present invention; FIG. 2 shows a partial structural schematic view of the cavity housing 100.

The present invention has been described in detail with reference to the accompanying drawings and embodiments.

1 is a schematic structural view of a plasma processing apparatus disclosed in the present invention, and more particularly, it relates to an inductively coupled plasma processing apparatus, which includes a cavity housing 100 and a reaction chamber 101, and a susceptor 150 is disposed in the reaction chamber 101. Used to support the substrate 200. The cavity housing includes an insulating window 110, and an inductor 105 is disposed above the insulating window 110. The inductor 105 generates a strong high-frequency alternating magnetic field under the action of a radio frequency power source (not shown), so that the low-pressure reactive gas Plasma is generated by ionization. A cavity cover 120 is disposed under the insulating window 110, and a cavity sidewall 140 is disposed under the cavity cover 120. To ensure that the substrate 200 can smoothly enter and exit the reaction cavity 101, the cavity sidewall 140 is disposed at a level similar to the upper surface of the base. Import and export 145. A vacuum pump 170 is disposed at the bottom of the chamber casing for discharging the reacted gas in the reaction chamber out of the reaction chamber. A plasma heating ring 130 is disposed between the cavity cover 120 and the cavity sidewall 140. A heating element is disposed in the plasma heating ring 130 for heating the plasma in the reaction chamber 101.

2 shows a partial structural schematic view of a cavity housing 100 between a cavity cover 120 and a cavity sidewall 140 with a heating element 135 disposed therein. Since the cavity cover 120 and the cavity sidewall 140 are both good conductors of heat, when the heating element 135 is operated, heat is not only supplied to the plasma inside the reaction chamber, but also is conducted upwards and downwards, which not only causes heat loss, but also Because the temperature of the cavity cover 120 and the cavity sidewall 140 is raised, the etching reaction process is smoothly performed. At the same time, the plasma heating ring 130 is in contact with the external space of the machine, and excessive heat will also affect the external space of the machine, and the safety of the operator. create a threat. In the structural diagram shown in FIG. 2, heat insulating channels 131, 132, and 133 are disposed around the heating element 135. In other embodiments, the number of heat insulating channels may be one or other quantities, and the heat insulating channels are disposed. It is possible to concentrate the heat of the heating element 135 into the reaction chamber. In this embodiment, considering the ease of processing, a method of providing three heat insulating channels is adopted, and the first heat insulating channel is a heat insulating channel having a certain depth on the side of the plasma heating ring 130 close to the cavity cover. 131. For convenience of production, the first embodiment of the present invention selects the first heat insulating channel 131 on the contact surface of the plasma heating ring 130 and the cavity cover 120. The width of the insulating channel 131 can be appropriately increased to ensure the heat and the cavity cover 120 as much as possible while ensuring ease and convenience of processing and installation. A second insulated channel 132 of a certain depth is disposed on a side of the plasma heating ring 130 adjacent to the sidewall 140 of the cavity. For convenience of fabrication, the second insulation channel 132 is selected to be disposed in the plasma heating ring 130 and On the contact surface of the cavity sidewall 140, the width of the second insulating channel 132 can be appropriately increased to ensure ease of processing and installation, so as to isolate heat from the cavity sidewall 140 as much as possible. The first insulated channel 131 and the second insulated channel 132 are substantially parallel. The heat insulating channel 133 is substantially perpendicular to the first heat insulating channel 131 and the second heat insulating channel 132. In this embodiment, the heat insulating channel 133 can communicate with the first insulating channel 131 and the second insulating channel 132. . It will be readily apparent to those skilled in the art that in other embodiments, the three insulated channels may also be disconnected.

In the reaction chamber 101, since the distribution range of the plasma is large, in order to ensure that as much plasma temperature as possible is controllable, the height of the plasma heating ring 130 needs to be the same as the height of the plasma region, due to the upper portion of the substrate 200. The plasma is involved in the etching reaction, so the plasma heating ring 130 needs to extend until the substrate 200 is substantially at the same level. In the actual process, since the plasma is directly in contact with the plasma heating ring 130, the plasma easily forms a precipitate on the inner surface of the plasma heating ring 130. In order to avoid contamination of the etching process by the precipitate, it is necessary to periodically heat the plasma. The ring 130 is taken out for surface cleaning. In order to reduce the plasma heating ring 130 The weight of the plasma heating ring 130 is unloaded and installed. In this embodiment, the end of the plasma heating ring 130 adjacent to the cavity cover 120 is the upper end 136, and the other end is the lower end 137. The radial width of the upper end 136 is greater than that of the lower end 137. Radial width. For ease of understanding, the cross-sectional structure of the plasma heating ring 130 can be visually depicted as an inverted "L" shape. The upper end 136 of the plasma heating ring 130 in this embodiment is placed above the cavity sidewall 140, and the lower end 137 is parallel to the cavity sidewall 140. To prevent deformation due to thermal expansion, a gap 138 is provided between the lower end 137 and the cavity sidewall 140. .

In another embodiment, the heat insulating channel may be a strip that is substantially arc-shaped and disposed around a side of the heating element adjacent to the outer space of the plasma heating ring 130. The heat insulating channel will heat the element 135. The heat is separated from the upper cavity cover 120, the lower cavity sidewall 140 and the external space, and the heat of the heating element 135 is mainly concentrated in the interior of the reaction chamber 101 to heat the plasma, thereby providing a good heat insulation effect.

In the embodiment of the present invention, the insulating window 110, the cavity cover 120, and the cavity sidewall 140 may be provided with heating elements according to the requirements of the process for the hardware. The present invention provides a separation between the plasma heating rings 130. The heat channel ensures that the temperature between the various components can be independently controlled while the heat is not lost, and the different requirements of the temperature of the reaction process at different positions are facilitated.

The present invention is disclosed in the above preferred embodiments, but it is not intended to limit the present invention, and any one skilled in the art can make possible variations and modifications without departing from the spirit and scope of the invention. The scope of protection should be determined by the scope defined by the claims of the present invention.

110‧‧‧Insulated window

120‧‧‧ cavity cover

130‧‧‧Plastic heating ring

131, 132, 133‧‧‧ insulated channels

135‧‧‧ heating element

136‧‧‧ upper end

137‧‧‧Bottom

138‧‧‧ gap

140‧‧‧ cavity sidewall

Claims (10)

A plasma processing apparatus includes: an insulating window and a cavity cover under the insulating window, a cavity sidewall disposed under the cavity cover, and a plasma heating between the cavity cover and the sidewall of the cavity a ring, wherein a heating element is disposed in the plasma heating ring for heating the plasma in a reaction chamber, at least one heat insulating channel is disposed around the heating element, and the heat insulating channel is disposed on the electric Grown inside the slurry heating ring to spatially isolate a portion of the plasma heating ring that contacts the reaction chamber from a portion of the plasma heating ring that contacts an outer space for use in the heating element The heat is concentrated inside the reaction chamber. The plasma processing apparatus according to claim 1, wherein at least two heat insulating channels are disposed around the heating element, and the first heat insulating channel is adjacent to a contact surface of the plasma heating ring and the cavity cover. The second heat insulating channel is adjacent to a contact surface of the plasma heating ring and the sidewall of the cavity, and the two heat insulating channels are substantially parallel. The plasma processing apparatus of claim 2, wherein a third insulating channel is further disposed around the heating element, the third insulating channel is substantially perpendicular to the first insulating channel and The second insulation channel. The plasma processing apparatus of claim 3, wherein the third heat insulating channel is disposed on a side of the heating element adjacent to an outer space of a reaction chamber of the plasma processing apparatus. The plasma processing apparatus of claim 4, wherein the third insulated channel is in communication with the first two insulated channels. The plasma processing apparatus of claim 1, wherein an insulating channel is disposed around the heating element, the heat insulating channel is an arc channel disposed around the heating element, and the heating element is disposed adjacent to the heating element One side of the outer space of a reaction chamber of the plasma processing apparatus. The plasma processing apparatus according to any one of claims 1 to 6, wherein the plasma heating ring is made of aluminum or an aluminum alloy. The plasma processing apparatus according to any one of claims 1 to 6, wherein the plasma processing apparatus is an inductively coupled plasma processing apparatus. The plasma processing apparatus according to any one of claims 1 to 6, wherein the plasma heating ring comprises an upper end adjacent to the cavity cover and a lower end adjacent to the sidewall of the cavity, the upper end having a radial width greater than The lower end radial width is described. The plasma processing apparatus of claim 9, wherein the lower end of the plasma heating ring and the side wall of the cavity are disposed in parallel with a certain gap therebetween.