KR20020018183A - Method and device for treating tabular substrates, especially silicon wafers for producing microelectronic elements - Google Patents

Abstract

The present invention relates to a method and apparatus for processing plate-like substrates, characterized in that the substrates are formed in a narrow gap between the two shields.

Description

METHOD AND DEVICE FOR TREATING TABULAR SUBSTRATES, ESPECIALLY SILICON WAFERS FOR PRODUCING MICROELECTRONIC ELEMENTS}

The present invention relates to a method and apparatus for processing a plate-like substrate, and more particularly to a silicon wafer for producing a microelectronic component according to the introduction in claims 1 and 6.

The surface of the substrate for electronic components, such as silicon wafers, must be very clean. This necessitates repeated cleaning processes during chip production. U.S. Application No. 5,468,302 discloses a method and apparatus for processing such substrates. EP application number 526 245 A1 also discloses an apparatus for cleaning a silicon wafer. In both devices, wafers are transferred and processed in the vertical direction. In this case, however, it turns out that a relatively large amount of processing fluid is required to clean the wafer.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide an apparatus and method for treating a wafer substrate without requiring a large amount of processing fluid.

In order to achieve the above object, the present invention is characterized in that the wafer is provided in a processing station in close proximity to the at least one shield (parallel) parallel to the wafer, the processing fluid is introduced into the wafer between the wafer and the shield A method of processing a wafer substrate is provided.

In addition, in order to achieve the above object, the present invention provides that at least one shield is provided at the processing station in parallel with and parallel to the wafer, a narrow gap is formed between the wafer and the shield, and at least one nozzle for injecting the processing fluid is provided. An apparatus having a receptacle and a processing station for holding a wafer in a vertical direction is provided, which is arranged in this gap.

A narrow gap is formed between the shield and the wafer and the shield is arranged in close proximity to the wafer in such a way that the processing fluid flows between the gap between the wafer and the shield, thereby requiring a relatively small amount of processing fluid. Moreover, the processing fluid is optimally used to treat the substrate surface. Because of the narrow gap, almost all processing fluids are used.

The shield rotates with the wafer to prevent the occurrence of turbulence between the wafer and the shield, ie within the gap. In this method, the processing fluid is removed from the wafer while spinning radially outward. The wafer drive and the shield drive may be coupled to each other or have a common drive.

According to a preferred embodiment, the processing fluid flows into the surface of the wafer at an angle not perpendicular to the surface direction of the wafer or 90 degrees. In addition, nozzles for injecting processing fluid may be pivotally engaged and / or displaced on the surface of the wafer. In this way, optimal cleaning of the wafer surface is particularly effective when the nozzle sweeps across the surface of the substrate in a computer controlled manner, similar to a scanner.

According to another preferred embodiment, the wafer is placed in a narrow gap between the two shields. In this method, both shields on the substrate surface can be processed simultaneously, thus saving considerable time. In addition, material stress and strain on the wafer are minimized when a heating or heat treating fluid is used. It is preferable that the shield has a spray opening for ejecting the ejected wafer, through which the processing fluid enters the wafer.

Preferably, the width of the gap between the wafer and the shield or two shields can be adjusted. In this method, there is an advantage that the flow rate of the processing fluid can be adjusted to an optimum value.

Additional points are caused when the shield is the same size, smaller or larger size than the wafer. In particular, the shield may be pot shaped and the wafer may be located within that port. In this embodiment, not only the sides of the wafer but also the edges can be cleaned without a special spray nozzle.

In yet another embodiment, the shield has guiding channels, such as spirals, panels, etc. to guide the processing fluid, on the side opposite the wafer. These guide flow paths prevent release of the processing fluid without the processing fluid being used, and guide the processing fluid through the processing channels to the surface of the substrate for effective cleaning.

In order to reduce the discharge flow rate of the processing fluid, the nozzle has a large diameter processing fluid outlet. The width of the outlet may range from 5% to 30% of the wafer diameter. The nozzle may then be displaced towards and away from the surface.

The shields may be spaced apart from one another to facilitate entry and removal of the wafer into the processing device. Thus, the narrow gap opens so that the removal device can grasp and remove the wafer. Means may be provided for treating the wafer with additional solution through one nozzle which may be introduced between the shields prior to the drying operation or the removal operation of the wafer.

The shield can be rotated in the same direction as the wafer or in the opposite direction. The shield may also be stationary.

For further objects and advantages of the invention, the features and detailed description of the invention can be seen from the following detailed description as well as from the dependent claims. In the detailed description, particularly preferred embodiments are described with reference to the drawings. The features shown in each figure and the features mentioned in the detailed description and claims can be embodied significantly in the invention individually or in any combination.

1 and 2 show a drying device having a spin chamber in an open and closed state.

3 shows a holding device with shields arranged to be displaceable.

4 illustrates a process of processing a substrate using additional nozzles.

FIG. 5 shows a configuration having a pot shaped shield; FIG.

6 shows a configuration with a nozzle having a relatively large diameter outlet.

7 illustrates a configuration having a displaceable nozzle.

Hereinafter, the accompanying drawings constitute a part of the specification and illustrate preferred embodiments of the present invention together with the above general description and the following detailed description of the preferred embodiments, and explain the principles of the present invention.

A drying station for spin drying 59 is shown in FIG. 1. The wafer, ie, the substrate 5, can be secured in the drying station 59 by a gripper 19 engaged with closed drying station 59 edge portions. The gripper can be rotated through the shaft 54. Drying station 59 has two parts 55 and 56 which can be separated for loading and discharging. The substrate (5) is rotated for drying purposes. The centrifugal force acting on the processing fluid is further supported by gravity on the droplets located on the substrate 5. In order to reduce the surface tension of water, a gas alcohol or gas-chemical mixture is introduced into the drying station 59 so that an alcohol or chemical environment is created in the drying station 59. The rotation of the water spins the surface of the substrate 5, which is then sucked by the suction device through the drain 57. According to the method, the overpressure present in the device is released.

For the purpose of reducing the concentration and amount of gaseous alcohol or gaseous compound used to reduce the surface tension of the wafer on the surface of the substrate 5 to be dried, two shields 60, 61 are provided in the drying station 59. And a gap 62 is formed between the two. Substrate 5 is located in this gap 62 proximate each shield 60, 61. The gaseous alcohol mixture flows through the shaft 54 or other shaft 54 'into the drying station, between the shield 60 and the substrate 5 and between the shield 61 and the substrate 5. After passing through the shaft 54 or other shaft 54 ′, the processing fluid is incident directly on the substrate surface and dispersed in the direction of the arrow 63.

In order to remove the substrate 5 from the drying station 59, the two parts 55, 56 are separated. Arm 64 is folded and the substrate is released for later transfer (see FIG. 2).

The shafts 54, 54 ′ may also be translated in the axial direction, in the direction of the arrow 65 or in the direction of another arrow 65 ′ (see FIG. 3). Thus, the substrate is likewise released when the gap 62 is enlarged to open the arm 64.

According to the embodiment shown in FIG. 4, additional nozzles 65 may be arranged between the shield and the substrate 5 at least after the displacement of the shield 60 to clean the surface of the substrate 5. The surface of the substrate 5 may be treated using a nozzle 58 disposed outside. This can be done after and / or before the drying process.

According to the embodiment of FIG. 5, the shield 60 is port shaped and has an edge 67 extending beyond the substrate 5 to guide the mixture 58 around the edge of the substrate. As a result, improved drying results can be obtained even at reduced spin rates.

6 discloses an embodiment in which the nozzle 68 for the introduction of the gas alcohol mixture has an enlarged cross section 69. In this method, the flow rate of the mixture is reduced as the turbulence velocity at the drying station 59 decreases.

FIG. 7 shows an embodiment in which the nozzle can be moved across the surface of the substrate 5 in the direction of the arrow 70. The nozzle can be pivoted and can be sprayed at different angles onto the surface of the substrate 5.

Liquids and gases, generally expressed as "fluid", may be injected using nozzles also provided on the shaft 54.

According to the above-described concept, the present invention has the advantage of providing an apparatus and a method capable of cleaning a wafer substrate without requiring a large amount of processing fluid.

Claims (14)

Plate-like substrates, in particular silicon wafers, are disposed substantially in a vertical direction and in which the wafers pass through at least one processing station in this vertical direction, at least one shield in which the wafers at the processing station are parallel to the wafer. And a processing fluid is introduced into the wafer between the wafer and the shield, the process fluid being disposed in proximity to the wafer and in particular the silicon wafers for producing microelectronic components. The method of claim 1, wherein the shield is rotated with the wafer. The method of claim 1 or 2, wherein the processing fluid flows into the surface of the wafer perpendicular to the surface of the wafer or at an angle other than 90 °. The method of claim 1, wherein the wafer is located in a narrow gap between two shields. 5. The method according to claim 1, wherein the wafer is ejected through the shield, in particular through an injection port. 10. An apparatus having a processing station and a receptacle for a wafer in a vertical direction, wherein at least one shield is located in the processing station in close proximity and parallel to the wafer, a gap is formed between the wafer and the shield, and the one or more nozzles are An apparatus for processing platelet substrates, in particular silicon wafers for producing microelectronic components, characterized in that it is arranged to inject processing fluid into the gap. 7. A device according to claim 6, wherein the width of the gap can be adjusted. 8. The apparatus of claim 6 or 7, wherein the shield is the same, smaller or larger than the size of the wafer. 9. The apparatus of any of claims 6-8, wherein the shield is port shaped and the wafer is disposed in the port. 10. The apparatus according to any one of claims 6 to 9, wherein the shield has guide flow paths such as spirals, panels, etc. for guiding the processing fluid on a surface facing the wafer. The device of claim 6, wherein the nozzle has a large diameter outlet for the processing fluid. 12. The apparatus of any one of claims 6 to 11, wherein the nozzle can be pivotally engaged, displaced or adjusted with respect to the surface of the wafer. 13. The apparatus of any one of claims 6-12, wherein multiple shields can be separated from one another to remove the wafer and to introduce the wafer into the processing station. 14. An apparatus according to any one of claims 6 to 13, wherein the shield can be rotated in the same direction or in the opposite direction relative to the rotating wafer.