JPH06103665B2 - Processor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a processing apparatus.

(Prior Art) Generally, a fine pattern for forming a semiconductor integrated circuit is formed, for example, by using a photoresist film of an organic polymer formed by exposure and development as a mask and etching a base film of this mask. Therefore, the photoresist film used as the mask needs to be removed from the surface of the semiconductor wafer after the etching process.

An ashing process is performed as a process for removing the photoresist film in such a case.

This ashing process is also used for removing resist, cleaning silicon wafers and masks, removing ink, removing solvent residues, etc., and is suitable when performing dry cleaning process in a semiconductor process.

There is an ashing device which generates oxygen atom radicals by irradiating with ultraviolet rays and performs the ashing process in a batch process.

FIG. 5 shows an ashing device for generating oxygen atom radicals by irradiating ultraviolet rays as described above. A large number of semiconductor wafers (2) are vertically arranged at a predetermined interval in a processing chamber (1) to perform processing. Ultraviolet rays from an ultraviolet arc tube (3) installed in the upper part of the chamber (1) are radiated through a transparent window (4) such as quartz provided on the upper surface of the processing chamber (1), and the processing chamber (1) The oxygen filled in is excited to generate ozone.

Then, oxygen radicals generated from the ozone atmosphere are caused to act on the semiconductor wafer (2) to perform the ashing process.

(Problems to be solved by the invention) However, in the conventional ashing apparatus using ultraviolet rays described above, the ashing speed is slow at 50 to 150 nm / min, and it takes a long time to perform the processing. Therefore, for example, in processing a large-diameter semiconductor wafer. There is a problem that a suitable single-wafer processing for processing semiconductor wafers one by one cannot be performed.

The present inventors have dealt with the above point and have developed an ashing process that has a high ashing speed of a photoresist film and can be used for single-wafer processing of large-diameter semiconductor wafers.

That is, ozone is used as the ashing gas, and this ozone gas is caused to flow to the surface of the semiconductor wafer to remove the unnecessary film. Since this device exhibits ashing characteristics due to ozone, it is not plasma-excited, but is heated at 150 to 500 ° C. on the wafer surface to be activated and perform an ashing reaction. In this ashing reaction, in order to show the best ashing characteristics in the range of 0.5 to 2.5 mm between the ashing gas outlet and the wafer surface, the mounting table on which the wafer is mounted is heated, the wafer is heated, and the wafer surface is heated. The ashing gas that comes into contact with is activated.

Therefore, the temperature of the mounting table becomes high, which affects surrounding devices.
For this reason, a device for cooling the unnecessary periphery of the mounting table is provided.

However, this cooling device has a large-scale structure whether it is air-cooled or liquid-cooled, and the device is large.

(Object of the Invention) The present invention has been made in consideration of the above points, and an object of the present invention is to provide a processing apparatus that can be downsized without using a special cooling device.

[Structure of Invention]

(Means for Solving Problems) The present invention relates to a processing apparatus for mounting and processing a substrate to be processed on a mounting table provided in a chamber, wherein the mounting table includes at least the mounting table and the processing target. It is characterized in that the outside of the contact portion with the substrate is covered with a heat insulating member.

(Function) By providing a mechanism having a heat insulating effect on at least a part of the mounting table on which the substrate to be processed is placed except for the contact portion of the substrate to be processed, peripheral devices can be provided at low cost without using a special cooling device. Can be insulated from. Moreover, since the special cooling device is not used, the entire processing device can be made compact.

(Example) An example in which the device of the present invention is applied to an ashing process in a semiconductor manufacturing process will be described below with reference to the drawings.
First, the configuration of the ashing device will be described.

A cylindrical upper chamber (5) having a U-shaped cross section is provided so as to be vertically movable by an elevator mechanism (not shown). On the central axis of the upper chamber (5), an outlet (6) for letting out the ashing gas, for example, a cylindrical nozzle having a diameter of 8 mm is provided. A disc (7) is provided on the same surface formed by the outlet (6). Cylindrical spacers (8) made of, for example, ceramic are provided at a plurality of places, for example, three places, on the lower surface of the peripheral portion of the disk (7). A lower chamber (9) is provided so as to engage with the upper chamber (5), and a packing (10) made of, for example, Teflon rubber is provided around the connecting portion of the upper chamber (5) with the lower chamber (9). It is set up. The packing (10) has a gentle L-shaped cross section, and is provided with its tip end facing outward so as to withstand the vacuum pressure from the inside of the chamber. When the packing (10) is partitioned from the inside of the chamber, a partition plate (1
1) is installed around. Then, in the lower chamber (9), a disc-shaped mounting table (12) having excellent ozone resistance is formed by, for example, alumite processing or Teflon processing that oxidizes aluminum and is configured to be temperature-adjustable by a temperature control mechanism (not shown). And a mechanism having a heat insulating effect, for example, a heat insulating material (13) made of myonite B, at least a part of the mounting table (12) excluding the contact portion with the substrate to be processed, for example, the mounting table (12).
Is provided on the bottom side of the. A substrate to be processed, for example, a semiconductor wafer 14 is set on the mounting table 12. When the semiconductor wafer (14) is transferred, an elevating mechanism (15) for elevating the semiconductor wafer (14) can be moved up and down by a cylinder (16) arranged in series, and the upward and downward movements can be performed on the periphery of the elevating mechanism (15). A plurality of pins (17), for example three, are provided, and the mounting table (12) is placed on the same circumference around the center point of the mounting table (12).
The semiconductor wafer (14) is provided so as to be movable up and down. The wrist pin (17) is made of a material having high heat resistance, for example, ceramic. An ozone generator (19) provided with an oxygen supply source (18) so that ashing gas flows out to the surface of the semiconductor wafer (14) is provided in the upper chamber (5) via a gas flow controller (20). It is connected to the outlet (6) of the circular plate (7).

Next, a method of ashing a semiconductor wafer by the above-mentioned ashing device will be described.

The upper chamber (5) is raised by the elevating mechanism and is transported into the lower chamber (9) by a transport mechanism (not shown) such as a hand arm. At this time, the wrist pin (17) is raised by the cylinder (16). Then, the semiconductor wafer (14) is placed on the wrist pin (17). After this, the tip of the wrist pin (17) is the mounting table (12).
The semiconductor wafer (14) descends to a position lower than the surface and
Is set on the table (12) described above.

Next, the upper chamber (5) descends and the lower chamber (9)
And the inside of the chamber is sealed. At this time, since the packing (10) provided at the connecting portion of the upper chamber (5) and the lower chamber (9) has a gentle L-shaped cross section, the upper chamber (5) and the lower chamber (9) are separated from each other. Even if the parallelism is slightly shifted, the processing chamber can be kept in a sealed state. Further, since the tip of the packing (10) faces outward, the packing (10) is strongly provided against the vacuum pressure from the inside of the chamber. However, since the packing (10) is also heated by the effect of heating the inside of the chamber, and the packing (10) is also ashed by the ashing gas, the partition plate (11) is provided in a state of partitioning from the inside of the chamber. Dissipates heat by means of the above packing (10)
Relieves heating.

Further, at the same time when the upper chamber (5) and the lower chamber (9) are connected, the cylindrical spacers (8) provided at a plurality of places, for example, three places, on the lower surface of the peripheral portion of the disk (7) are provided on the semiconductor wafer (14). Contact the mounting surface. The spacer (8) is provided such that the distance between the disk (7) and the semiconductor wafer (14) at the time of contact with the mounting surface of the semiconductor wafer (14) is, for example, about 0.5 to 200 mm. The desired spacing can always be obtained by contact between the spacer (8) and the mounting table (12).

At this time, the semiconductor wafer (14) is already simultaneously heated by heating the mounting table (12) to, for example, about 300 ° C. by a temperature control mechanism (not shown). For the purpose of preventing heat from being dissipated to the periphery of the chamber due to this heating, at least a part of the mounting table (9) excluding the semiconductor wafer (14) contact portion, for example, a mechanism having a heat insulating effect on the bottom side of the mounting table (12), such as myonite Since the heat insulating material (13) is provided, heat can be insulated from surrounding devices.

Then, on the heated semiconductor wafer (14), the ashing gas generated by the ozone generator (19) provided with the oxygen supply source (18) is flowed by the gas flow controller (20) at a flow rate of, for example, 3 to 15 l / It is adjusted to about min, flows out from the outlet (6) of the disc (7), and is ashed. At this time, if the mounting table (12) is made of aluminum,
Since the surface is oxidized by the ashing gas, the surface is anodized or Teflon processed to improve the ozone resistance.

The ashing gas is caused to flow radially and uniformly from the center of the semiconductor wafer (14) to the surface of the semiconductor wafer (14) mounted on the mounting table (12) through the outflow port (6). Ashing process is performed.

Then, the ashing gas after the ashing process is decomposed by an ozone decomposer (not shown) and exhausted from the exhaust pipe (21).

Next, another embodiment of the device of the present invention will be described with reference to FIG. A Teflon-based rubber packing (10), for example, is provided around the peripheral portion of the upper chamber (5) that is vertically movable by an elevator mechanism (not shown). The packing (10) has a gentle L-shaped cross section, and is provided with its tip end facing outward so as to withstand the vacuum pressure from the inside of the chamber. Spacers (8) are provided adjacent to the packing (10) at a plurality of places, for example, three places, and a lower chamber (9) is provided so as to engage with the spacer (8) and the packing (10). A mechanism having a heat insulating effect, for example, a mounting table (12) on which a heat insulating material (13) made of myonite B is laid is provided in the central portion of the lower chamber (9) so that a substrate to be processed, for example, a semiconductor wafer (14) can be mounted. It is configured. For example, a glass disk (7) supported by the upper chamber (5) is arranged at a position facing the mounting table (12). An outlet (6) having a diameter of 8 mm, for example, for letting out ashing gas is provided at the center of the disc (7), and a device is provided via a gas supply pipe (22) connected to the outlet (6). It is connected to an ozone generator (not shown) provided with an oxygen supply source provided outside.
The gas supply pipe (22) is vertically provided at the center of the disc (7), and the adjusting screws (23) provided at a plurality of places, for example, three places, of the adjusting mechanism provided on the disc (7). The height and angle of the disc 7 can be adjusted by adjusting.

In the ashing device having the above structure, first, the upper chamber (5)
And the semiconductor wafer (14) is transferred onto the mounting table (12) by a transfer mechanism (not shown) and mounted on a predetermined position. Then, the upper chamber (5) is lowered and airtightly connected to the lower chamber (9). At this time, the chamber is kept airtight by the packing (10) provided between the chambers. A spacer (8) provided adjacent to the packing (10) always keeps the distance between the upper chamber (5) and the lower chamber (9) constant, and at this time, mounts on the mounting table (12). The adjustment screw (23) is set in advance so that the distance between the semiconductor wafer (14) and the disk having the gas outlet (6) is 0.1 to 20 mm, for example, 0.5 mm. This interval is shown in FIG. 4, which shows the change in the ashing rate due to the change in the interval. The vertical axis represents the ashing rate, the horizontal axis represents the wafer diameter, and the position 0 on the horizontal axis represents the center of the wafer. Since this characteristic changes depending on the ashing gas flow rate, the interval corresponding to the gas flow rate is 0.1 to 20 mm.
It is appropriately selected within the range of degree. Next, the semiconductor wafer (14) mounted on the mounting table (12) is heated to 150 to 500 ° C. by a heating mechanism (not shown), for example, a heater built in the mounting table (12).
For example, it is heated to 300 ° C. At this time, since there is a risk that the surrounding equipment and the like will be damaged by heating due to the heating of the mounting table (12), a mechanism having a heat insulating effect, such as a myonite B heat insulating material (13), is attached to the bottom of the mounting table (12). Install and insulate from surrounding equipment. Further, as shown in FIG. 3, the heat insulating material (13) is provided on a portion of the supporting surface of the mounting table (12) supporting the semiconductor wafer (14) except the contact portion with the semiconductor wafer (14), the bottom surface and the side surface. It is even more effective to insulate the surrounding equipment.

Next, with the semiconductor wafer (14) in the above-mentioned heated state, an ashing gas containing ozone generated by an ozone generator (not shown) equipped with an oxygen supply source is located at the center of the disc (7). The resist film flowing out from (6) and adhering to the surface of the substrate to be processed is removed by ashing.

In the above-described embodiment, the heat insulating mechanism is made of the myonite B heat insulating material. However, the same effect can be obtained by using ceramic, silicon rubber, mycarex or the like. Further, the same effect can be obtained even if the heat insulating mechanism is provided in multiple layers and used.

As described above, according to this embodiment, a mechanism having a heat insulating effect is provided in at least a part of the mounting table except for the contact portion with the semiconductor wafer, so that the surrounding device can be operated without using an external cooling mechanism or the like. Since it can be insulated, the entire device can be made compact.

〔The invention's effect〕

As described above, according to the present invention, a special cooling device is used by providing a mechanism having a heat insulating effect on at least a part of the mounting table on which the substrate to be processed is placed, excluding the substrate contact portion. Insulation from surrounding equipment can be achieved at low cost without any cost. Moreover, since the special cooling device is not used, the entire processing device can be made compact.

[Brief description of drawings]

FIG. 1 is a block diagram of an ashing device for explaining an embodiment of the device of the present invention, FIG. 2 is a block diagram of an ashing device for explaining another embodiment of the device of the present invention, and FIG. FIG. 4 is a diagram for explaining another shape of the mechanism, FIG. 4 is a graph showing changes in the ashing rate due to changes in the distance between the semiconductor wafer and the disk, and FIG. 5 is a conventional ashing device. 12 …… Mounting table, 13 …… Insulation material 14 …… Semiconductor wafer

Claims (1)

[Claims] 1. A processing apparatus for mounting and processing a substrate to be processed on a mounting table provided in a chamber, wherein the mounting table has a heat insulating member at least outside a contact portion between the mounting table and the processing substrate. A processing device characterized by being covered with.