JP2016186994A - Substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent iron and particles from remaining on a substrate after processing in a substrate processing apparatus in which a process liquid as an organic solvent is supplied from a container formed by stainless steel.SOLUTION: A substrate processing apparatus 1 comprises: a container 92 which is connected to a connection part 126 and formed by stainless steel, for storing IPA 91 as a process liquid; a processing part 11 to which the IPA 91 is introduced via a supply route 121 in which processing in the processing part 11 includes a drying treatment of a substrate 9 by the IPA 91; a first particle removal filter 122, a metal removal filter 123 and a second particle removal filter 124 which are provided on the supply route 121 in this order. This prevents iron and particles from remaining on the substrate 9 after the processing.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique for processing a substrate by supplying a processing liquid to the substrate.

  Conventionally, in the manufacture of devices, processing is performed by supplying various processing liquids to substrates for various uses such as a semiconductor substrate and a glass substrate. Since a very fine pattern is formed on the substrate, it is required to keep the surface of the substrate clean. In particular, thorough removal of metal impurities such as metal particles and metal ions from the processing liquid is important in improving the quality and reliability of the device obtained from the substrate.

  For example, in the semiconductor substrate cleaning apparatus disclosed in Patent Document 1, metal impurities are adsorbed by a filter.

JP-A-8-8223

  When the semiconductor substrate is washed with a processing solution contaminated with metal impurities, the semiconductor substrate is contaminated with metal. Therefore, in order to exclude metal particles and metal ions, a particle removal filter and an ion exchange membrane that is a metal removal filter are used. However, it has become clear that metal impurities and particles may not be sufficiently removed by simply connecting these two filters in series. In particular, when the treatment liquid, which is an organic solvent, is supplied from a container formed of stainless steel, both iron impurities and particles cannot be effectively removed.

  This invention is made | formed in view of the said subject, and aims at suppressing that iron and a particle remain on the board | substrate after a process.

  The invention according to claim 1 is a substrate processing apparatus, wherein a connecting portion to which a container formed of stainless steel for storing a processing liquid that is an organic solvent is connected, and the processing liquid is supplied to the substrate to supply the processing liquid. A processing section that performs processing on the substrate; a supply path that guides the processing liquid from the connection section to the processing section; a first particle removal filter provided on the supply path; the first particle removal filter; and the processing section. A metal removal filter that is provided on the supply path and removes at least iron ions contained in the processing liquid; and a second particle removal provided on the supply path between the metal removal filter and the processing unit. And a filter.

  A second aspect of the present invention is the substrate processing apparatus according to the first aspect, wherein the processing liquid is isopropyl alcohol.

  A third aspect of the present invention is the substrate processing apparatus according to the second aspect, wherein the treatment with the treatment liquid is a drying treatment for the substrate.

  Invention of Claim 4 is the substrate processing apparatus in any one of Claim 1 thru | or 3, Comprising: The average pore diameter of the said 1st particle removal filter is from the average pore diameter of the said 2nd particle removal filter. Is also big.

  A fifth aspect of the present invention is the substrate processing apparatus according to any one of the first to fourth aspects, further comprising another processing unit that supplies a processing liquid to the substrate and performs processing on the substrate, A supply path extends from the connection section, a common flow path, a branch flow path that guides the processing liquid from the common flow path to the processing section, and another branch flow path that guides the processing liquid from the common flow path to the other processing section The first particle removal filter and the metal removal filter are provided in the common channel, the second particle removal filter is provided in the branch channel, and another second channel is provided in the other branch channel. A particle removal filter is provided.

  A sixth aspect of the present invention is the substrate processing apparatus according to any one of the first to fifth aspects, wherein the buffer is disposed on the supply path between the metal removal filter and the second particle removal filter. A tank is further provided.

  According to the present invention, iron and particles can be prevented from remaining on the substrate after processing.

It is a figure which shows schematic structure of a substrate processing apparatus. It is a figure which compares and shows the iron detected from IPA by the combination of a filter. It is a figure which shows schematic structure of another substrate processing apparatus.

  FIG. 1 is a diagram showing a schematic configuration of a substrate processing apparatus 1 according to an embodiment of the present invention. The substrate processing apparatus 1 supplies various processing liquids to the substrate 9 and processes the substrate 9. The process includes a drying process for the substrate 9. Specifically, a process of supplying and cleaning pure water to the substrate 9 and a process of supplying IPA (isopropyl alcohol) to the substrate 9 and replacing the pure water with IPA to dry the substrate 9 are included. . In FIG. 1, only the portion related to the supply of IPA is shown in the processing liquid supply system in the substrate processing apparatus 1. The actual substrate processing apparatus 1 is provided with a large number of pipes.

  The substrate processing apparatus 1 includes a processing unit 11 and a supply system 12 that guides the processing liquid to the processing unit 11. The processing unit 11 performs processing by supplying a processing liquid to the substrate 9. The processing unit 11 includes a rotating unit 111 that rotates the substrate 9 in a horizontal posture, a supply unit 112 that supplies a processing liquid to the upper surface of the substrate 9, and a liquid receiving unit 113 that receives the processing liquid scattered from the substrate 9. . The processing liquid received by the liquid receiving part 113 is discarded. Other structures may be employed as the processing unit 11. In the present embodiment, the processing unit 11 is a single wafer type, but may be a batch type.

  The supply system 12 includes a supply path 121, a first particle removal filter 122, a metal removal filter 123, a second particle removal filter 124, a valve 125, a connection portion 126, and a pump 127. The first particle removal filter 122 is provided on the supply path 121. The metal removal filter 123 is provided on the supply path 121 between the first particle removal filter 122 and the processing unit 11. The second particle removal filter 124 is provided on the supply path 121 between the metal removal filter 123 and the processing unit 11.

  The valve 125 is provided on the supply path 121 between the metal removal filter 123 and the second particle removal filter 124. One end of the supply path 121 is connected to the processing unit 11. The connection part 126 is located at the other end of the supply path 121. The pump 127 is provided on the supply path 121 between the connection portion 126 and the first particle removal filter 122. The container 92 is connected to the connection portion 126. Precisely, a connection portion 922 provided at an end portion of the pipe 921 attached to the container 92 is connected to the connection portion 126 of the supply system 12.

  The container 92 stores the IPA 91 in a sealed state. However, in order to take out the IPA 91, inflow of gas into the container 92 is allowed. The container 92 is formed of stainless steel for explosion protection. When the pump 127 is driven with the valve 125 opened, the IPA 91 is sucked up from the container 92, and the IPA 91 is guided from the connection part 126 to the processing part 11 through the supply path 121. The IPA 91 sequentially passes through the first particle removal filter 122, the metal removal filter 123, and the second particle removal filter 124.

  The first particle removal filter 122 and the second particle removal filter 124 remove particles contained in the IPA 91. The metal removal filter 123 is an ion exchange membrane in the present embodiment, and removes metal ions contained in the IPA 91. As described above, the IPA 91 is used during the drying process for the substrate 9. By removing the metal ions from the IPA 91, it is possible to suppress the metal from remaining on the substrate 9 after drying. In particular, prevention of residual metal is effective when the drying process is the last step in the processing unit 11.

  The average pore diameter of the first particle removal filter 122 is larger than the average pore diameter of the second particle removal filter 124. Thereby, particles can be efficiently removed while using an inexpensive first particle removal filter 122.

  Next, the effect obtained by arranging the three filters 122, 123, and 124 in this order will be described.

  FIG. 2 shows the iron level detected from the IPA after passing through the filter when the particle removal filter or the metal removal filter is arranged in various orders on the supply path in an apparatus similar to the apparatus of FIG. It is a figure which compares and shows the density | concentration of a particle and an iron ion. Although other metal ions are included in IPA, since container 92 is formed of stainless steel, a large amount of iron is included when not passing through a filter. Therefore, FIG. 2 shows only the results for iron.

  In the graph, “P” indicates that a particle removal filter is disposed on the supply path. “M” indicates that a metal removal filter is disposed on the supply path. “→” indicates the arrangement order of the filters. For example, “P → P” indicates that two particle removal filters are arranged in series from the upstream side toward the processing unit. “P → M” indicates that the particle removal filter and the metal removal filter are arranged in series in this order from the upstream side toward the processing unit.

  In FIG. 2, the iron detection level is the lowest when “P → P → M”, and the iron detection level is low when “P → M” and “P → M → P”. From this, it can be said that the iron detection level can be lowered by arranging the metal removal filter downstream of the particle removal filter. However, in practice, in the case of “P → P → M” and “P → M”, the particle detection level increases. This is considered to be caused by generation of particles other than metal from the metal removal filter.

  In the case of “P → M → P”, metal particles and non-metal particles are removed by the first particle removal filter, and metal ions are removed by the metal removal filter. Then, particles other than metal generated by the metal removal filter are removed by the last particle removal filter. That is, by arranging the particle removal filter, the metal removal filter, and the particle removal filter in this order, it is possible to effectively remove all of the metal particles, particles other than metal, and metal ions.

  Therefore, in the substrate processing apparatus 1, the first particle removal filter 122, the metal removal filter 123, and the second particle removal filter 124 are arranged on the supply path 121 in this order. When the IPA 91 flows from the container 92 made of stainless steel through the supply path 121, generation of particles other than metal is suppressed while removing iron particles and iron ions contained in the IPA 91. As a result, iron and particles are prevented from remaining on the substrate 9 after processing.

  Further, the first particle removal filter 122 is provided as a filter for removing particles contained in the processing liquid, and the second particle removal filter 124 is provided as a filter for removing particles generated from the metal removal filter 123, thereby removing particles. It is possible to use a filter adapted to the above. For example, in the present embodiment, a filter suitable for removing metal particles and large particles is used as the first particle removal filter 122, and a filter suitable for removing particles other than metal and small particles is used as the second particle removal filter 124. Can be used.

  FIG. 3 is a diagram illustrating the substrate processing apparatus 1 when a plurality of processing units 11 are provided. The configuration and operation of each processing unit 11 are the same. In the substrate processing apparatus 1 of FIG. 3, the supply system 12 is provided with a buffer tank 133 and a pump 134. Other components are the same as those in FIG. 1, and are denoted by the same reference numerals as those in FIG.

  The supply path 121 includes a first supply path 131 that extends from the connection portion 126 to the buffer tank 133, and a second supply path 132 that extends from the buffer tank 133 to each processing unit 11. In other words, the buffer tank 133 is disposed on the supply path 121. In the first supply path 131, a pump 127, a first particle removal filter 122, and a metal removal filter 123 are sequentially arranged from the connection portion 126 toward the buffer tank 133.

  The second supply path 132 branches in the middle and is connected to each processing unit 11. Hereinafter, a portion of the supply path 121 extending from the connection portion 126 to the branch position 135 is referred to as a “common flow path 141”, and a portion from the branch position 135 to each processing unit 11 is referred to as a “branch flow path 142”. The first supply path 131 is included in the common flow path 141. The pump 134 is provided between the buffer tank 133 and the branch position 135 on the common flow path 141. Each branch flow path 142 is provided with a valve 125 and a second particle removal filter 124 in order from the branch position 135 toward the processing unit 11. When the pump 134 is driven, the IPA 91 is guided from the common channel 141 to the processing unit 11 via the branch channel 142.

  As described above, the first particle removal filter 122 and the metal removal filter 123 are provided in the common flow path 141. The plurality of second particle removal filters 124 are respectively provided in the plurality of branch channels 142. By providing the second particle removal filter 124 immediately before each processing unit 11, the IPA 91 from which particles are appropriately removed can be easily supplied to the substrate 9.

  In particular, when the buffer tank 133 is provided, it is preferable that the buffer tank 133 is provided between the metal removal filter 123 and the second particle removal filter 124. Since the metal generation source is mainly the container 92, the IPA 91 from which the metal has been removed can be stored in the buffer tank 133 by providing the metal removal filter 123 in front of the buffer tank 133. Further, by providing the second particle removal filter 124 behind the buffer tank 133, the influence of various particle generation sources including the buffer tank 133 can be removed immediately before the processing.

  Since the buffer tank 133 is provided on the downstream side of the metal removal filter 123, the buffer tank 133 is preferably a container made of resin or having a resin layer formed on the inner surface.

  The substrate processing apparatus 1 can be variously modified.

  The treatment liquid that is an organic solvent supplied in a container 92 formed of stainless steel is not limited to IPA. Further, the use of the treatment liquid is not limited to drying. Examples of the treatment liquid may include ketones (acetone, diethyl ketone, etc.), ethers (methyl ether, ethyl ether, etc.), and polyhydric alcohols (ethylene glycol, etc.).

  In FIG. 3, the buffer tank 133 may be omitted. Conversely, a buffer tank may be provided in the substrate processing apparatus 1 of FIG.

  The positional relationship between the valve 125 and the filter may be changed as appropriate. Further, a plurality of filters may be provided substantially in one filter device. For example, the first particle removal filter 122 and the metal removal filter 123 may be provided in the cover of one filter device. The metal removal filter 123 and the second particle removal filter 124 may be provided in the cover of one filter device. Furthermore, the first particle removal filter 122, the metal removal filter 123, and the second particle removal filter 124 may be provided in this order in the cover of one filter device.

  The first particle removal filter 122 and the second particle removal filter 124 may be the same filter. As the particle removal filter, a resin or another material may be used. The metal removal filter 123 may selectively remove iron ions. The metal removal filter 123 only needs to remove at least iron ions contained in the treatment liquid. The metal removal filter 123 may be a chelate resin.

  The substrate 9 is not limited to a semiconductor substrate or a glass substrate, and may be a substrate made of another material. The substrate 9 may be used for various purposes.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 9 Substrate 11 Processing part 91 IPA (processing liquid)
92 Container 121 Supply path 122 1st particle removal filter 123 Metal removal filter 124 2nd particle removal filter 126 Connection part 133 Buffer tank 141 Common flow path 142 Branch flow path

Claims (6)

A substrate processing apparatus,
A connection part to which a container formed of stainless steel for storing a treatment liquid which is an organic solvent is connected;
A processing unit for supplying a processing liquid to the substrate and processing the substrate;
A supply path for guiding the processing liquid from the connection part to the processing part;
A first particle removal filter provided on the supply path;
A metal removal filter that is provided on the supply path between the first particle removal filter and the processing unit and removes at least iron ions contained in the processing liquid;
A second particle removal filter provided on the supply path between the metal removal filter and the processing unit;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
The substrate processing apparatus, wherein the processing liquid is isopropyl alcohol. The substrate processing apparatus according to claim 2,
The substrate processing apparatus, wherein the treatment with the treatment liquid is a drying treatment for the substrate. A substrate processing apparatus according to any one of claims 1 to 3,
The substrate processing apparatus, wherein an average pore diameter of the first particle removal filter is larger than an average pore diameter of the second particle removal filter. The substrate processing apparatus according to claim 1, wherein:
Further comprising another processing unit for supplying a processing liquid to the substrate and processing the substrate,
The supply path is
A common flow path extending from the connecting portion;
A branch channel for guiding a processing liquid from the common channel to the processing unit;
Another branch channel for guiding the processing liquid from the common channel to the other processing unit;
Including
The first particle removal filter and the metal removal filter are provided in the common flow path,
The second particle removal filter is provided in the branch channel,
A substrate processing apparatus, wherein another second particle removal filter is provided in the other branch channel. A substrate processing apparatus according to any one of claims 1 to 5,
The substrate processing apparatus further comprising a buffer tank disposed on the supply path between the metal removal filter and the second particle removal filter.

Images