JPH0144011B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a resist developing method used in a photolithography process of semiconductor manufacturing. Structure of conventional example and its problems When selectively etching silicon, glass substrates, various material films, etc. on the substrate, in photomask production in semiconductor device manufacturing and photolithography process in semiconductor process, a resist serving as a mask is placed on the substrate. Forming a layer is performed. This resist layer is formed into a pattern through steps such as coating, exposure, and development. In particular, as the use of positive resists has become widespread in semiconductor manufacturing processes in recent years, the quality of the developing process has come to determine the fate of resist patterns. Conventionally, developing methods include immersing a silicon substrate, mask plate, etc. after resist exposure (hereinafter simply referred to as a sample) in a chemical bath filled with a developer (hereinafter referred to as the dip method), and immersing a sample in a spinner. There is a method (hereinafter referred to as a spray method) in which a developing solution is spouted in the form of a mist from a nozzle while the developer is placed on top and rotated. In general, the dip method has advantages such as being able to develop a large amount of sample at once and being able to maintain the temperature of the developer at a constant level. There are drawbacks.
The spray method has the advantage that the sample is less likely to become contaminated, but has disadvantages such as the inability to process a large number of samples at once and the difficulty in controlling the end point of development. Furthermore, when development takes a long time for electron beam resists, etc., the developer is sprayed out in the form of a mist, which causes the development temperature to drop rapidly and prevent development from proceeding.The baking time after development is long, requiring a long belt system. There are problems such as the need for an oven. OBJECTS OF THE INVENTION The present invention aims to eliminate these drawbacks and provide a resist developing method capable of obtaining a good resist pattern. Structure of the Invention The present invention is a resist developing method in which a resist layer is developed and patterned in a liquid such as a developer and a rinse solution that flows down in a thin laminar flow along the surface of the resist layer. According to the present invention, continuous processing is possible, and resist development can be performed quickly using a relatively simple device. DESCRIPTION OF EMBODIMENTS In the resist development method according to the present invention, continuous
Alternatively, the sample is sent to the developing section intermittently at predetermined intervals. In this developing section, the developer is spouted in a mist or shower form from a nozzle with one or more holes, and is changed into a thin laminar flow at a location other than the sample surface without directly contacting the resist surface of the sample. Expose inside. For rinsing, expose the rinsing liquid to the same laminar flow. After rinsing, dry it by exposing it to a drying liquid. Furthermore, it consists of a series of steps of heating the sample at a predetermined temperature from the front or back side. In this development method, the sample is always developed in a clean laminar flow, so the sample does not become smudged as occurs in the dip method, and the developer temperature can be kept constant.
Good reproducibility of development conditions. The end point of development can be detected through the laminar flow of developer. Since there is no need to remove the sheets one by one from the spinner as in the spray method, continuous processing is possible and the device has the advantage of being simple in structure. Next, an apparatus for implementing the resist developing method according to the present invention will be described in detail with reference to the drawings. FIG. 1a is a front view of an apparatus for implementing the resist developing method according to the present invention, and FIG. 1b is a cross-sectional view taken along line A-A'. In Fig. 1, 1 is a sample loading chamber, 2 is a sample loading chamber;
3 is a developing chamber, 3 is a rinsing chamber, 4 is a drying chamber, 5 is a baking chamber, and 6 is a sample unloading chamber. Each room is separated by partition walls 7-1 to 7-4,
Each of the partition walls 7-1 to 7-4 has a window-like cut 8 of the minimum size necessary for the movement of the sample.
-1 to 8-5 are provided. The developing chamber 2 and the rinsing chamber 3 are provided with nozzles a-1 and a-2, respectively, and the drying chamber 4 is provided with a gas blowing nozzle 9-.
3 is provided. 10 is a belt for transporting the sample. The belt 10 is provided with a sample holding frame 11, and the frame 11 is formed into a concave or convex shape depending on the shape, size, and thickness of the sample. As a whole, the sample moves continuously or intermittently from the loading chamber 1 toward the drying chamber 4 as the sample conveying belt 10 moves. Further, 12 is a sample, and 13 is a laminar flow of developer, which flows down onto the sample holding section 11 or the surface of the sample 12. 14 is a laminar flow generating section for converting the developer coming out from the nozzle 9-1 into a laminar flow 13. 15 is a sensor for detecting the end point of development. 16 is sample 12
This is a resist layer coated on the surface. 17 is a developer,
A gutter for collecting rinse liquid and a filter (not shown)
connected to each other. Figure 1c shows the sample holding frame 11 in Figure 1b.
18 is a driving chain, 19 is a driving gear, and 20 is a motor. The belt 10 provided with the sample holding frame 11 is in close contact with the drive chain 18. When the rotation of the motor 20 is transmitted to the belt 10 via the driving gear 19, the sample holding frame 11 moves continuously or intermittently at predetermined intervals, and the moving speed is determined by the sensor 15 that detects the end point of development. Determined by the movement stop signal from. Next, the operation of this device will be explained. The sample 12 carried into the developing chamber 2 from the loading chamber 1 is covered with a laminar flow 13 as it is carried in.
A required pattern is formed on the resist layer 16. Sensor 1 detects the end point of the resist pattern state
5, and it is also controlled by changing the development time due to changes in belt movement speed. Partition wall 7-
The sample 12 that has passed through 2 enters the rinsing chamber 3 and is rinsed. After rinsing, the sample is exposed to gas emitted from the nozzle 7-3 in the drying chamber 4. Further, it passes through a baking chamber 5 and is stored in a cassette in an unloading chamber 6. With the above configuration, since the developer temperature can be kept constant, the reproducibility of the development conditions is improved. Figure 2a shows the relationship between the appropriate exposure amount and development temperature when using an electron beam resist.
This shows the case of MiBK/iPA=2/1 300sec development. When the temperature falls below the lower limit temperature for development, granular residues are generated on the sample surface from which the resist layer 16 has been removed by development. On the other hand, when the temperature exceeds the upper limit, film burrs occur. Figure 2b shows an example of measuring the temperature distribution of sample A when developed by the spray method and the temperature distribution of sample B when developed according to the present invention. It can be seen that the width of the distribution is wide, but it is narrowed by the method according to the present invention. In the case of development by a spray method, the resist layer 16 may be developed into a ring shape or granular residue may be generated. Table 1 shows an example of a comparison of the development times by the dip method, the spray method, and the method according to the present invention, and it can be seen that the method according to the present invention shortens the development time compared to the spray method. It can also be seen that the time required to process a certain number of sheets is short. Furthermore, it can be seen that the number of defects is smaller compared to the dip method.

[Table] As mentioned above, in the embodiments of the present invention,
Although the developing solution and the rinsing solution are spouted from respective nozzles, a structure may also be adopted in which the solutions gush out in close contact with the laminar flow generating section. Drying may be performed using a spinner. For baking, in addition to a resistance heating type hot plate type, an infrared heater may be used. It goes without saying that the developing nozzle may have a structure that allows the nozzle itself to move along the sample surface so that it can be used in conjunction with spray development or can be switched. Effects of the Invention As explained above, according to the present invention, the reproducibility of development conditions is good and the throughput of samples is increased. Sample contamination is reduced. There are many advantages such as easy detection of the end point of development and automation of development.

[Brief explanation of drawings]

1A, 1B, and 1C are a front view, a sectional view, and an explanatory view of the main mechanism of a developing device according to an embodiment of the present invention, and FIGS. 2A and 2B are characteristic diagrams showing the effects of the present invention. 1...Sample loading chamber, 2...Development chamber, 3
... Rinse room, 4 ... Drying room, 5 ... Baking room, 6 ... Sample unloading room, 7-1 to 7
-4...Partition wall, 9-1 to 9-3...Nozzle, 11
... Sample holding frame section, 12 ... Sample, 13 ... Laminar flow, 14 ... Laminar flow generation section.

Claims (1)

[Scope of Claims] 1. A sample having an exposed resist layer is placed on the sample holder of a strip-shaped sample transporter in which sample holders are arranged in a row along the longitudinal direction, with the resist surface facing upward. After the arrangement, the strip-shaped sample carrier is tilted in a direction perpendicular to its longitudinal direction, and is continuously or intermittently moved into a developing chamber in which a nozzle for supplying developer is arranged, and the developer is supplied from the nozzle. A resist developing method comprising: causing a developing liquid to flow down along the resist surface to form a laminar flow, and forming a resist pattern on the surface of the sample in the laminar flow. 2. The resist developing method according to claim 1, wherein the width of the laminar flow of the developing liquid flowing down is greater than the thickness of the laminar flow.