JPH0465114A - Resist developing solution inspection device - Google Patents

Abstract

PURPOSE:To detect a developing condition of a resist film by a developing solution based upon a change in a vibration resonance frequency by dipping the piezoelectric vibration on which the resist film is deposited into the resist developing solution. CONSTITUTION:A piezoelectric vibrator 4 is constructed by providing electrodes 2, 3 facing each other on opposite surfaces of a disk-shaped substrate 1 comprising crystal and the like. A resonance frequency of the piezoelectric vibrator 4 is monitored by dipping the piezoelectric vibrator 4 which surface is coated with a resist film 6 in a developing solution 7 and developing the resist film 6. With such construction, deterioration of the resist developing solution, i.e., the developing ability of the developing solution can be known by a change in the resonance frequency of the piezoelectric vibrator.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an inspection device for a resist developer used in phosphorography technology essential for manufacturing semiconductor devices.

(B) Conventional Technology In recent years, the semiconductor industry, especially the fields of IC and LSI manufacturing, has made remarkable progress, with rapid progress toward higher densities and higher integration.

What supports the development of these technologies is microfabrication technology, especially phosphorography technology using resist.

Generally, microfabrication using a resist incorporates a wet development method during the process. The wet development method is carried out using a developer, but the wet development process has a large influence on microfabrication technology using, for example, a positive resist made of a polymeric material. This is because the pattern forming method for positive resists is based on the difference in dissolution rate in a developer between exposed areas and unexposed areas by exposure to radiation such as ultraviolet rays, deep ultraviolet rays, X-rays, and electron beams. That is, as shown in FIG. 4, the molecular weight of the exposed area 11 of the radiation [O] is lower than that of the unexposed area 12, so that the exposed area 11 is dissolved in the developer faster and a pattern is formed.

(c) Problems to be Solved by the Invention The wet development process using this developer is influenced by its various conditions, such as the deterioration status of the developer, the developing temperature, and the developing time. Although the developing temperature and developing time can be accurately controlled, there is no way to monitor the deterioration status of the developing source, the lifespan of the developing solution, or the developing ability, and there is no real control. The only way to know the status of the developer was to run it.

(d) Means for Solving the Problems The present invention has been made in view of the above problems, and includes a resist film developed with a resist developer to be inspected on the surface of a piezoelectric vibrator made of a ferroelectric material. The vibrator on which this resist film is adhered is immersed in a resist developer to be inspected, and the state of development of the resist film by the developer is detected by the frequency change of the vibrator.

(E) Function According to the present invention, the state of deterioration of the resist developer, ie, the developing ability of the developer, can be known from changes in the resonance frequency of the piezoelectric vibrator.

(f) Example FIG. 1 is a conceptual diagram showing the configuration of the resist developer testing apparatus of the present invention, and FIG. 2 is an enlarged side view of the main parts thereof. It is a disk-shaped substrate made of a ferroelectric material such as ferroelectric material, and has electrodes 2.3 facing each other on both the front and back surfaces, and is a so-called piezoelectric vibrator 4.
It consists of 5 is an oscillation circuit connected to this picture electrode 2.3. 6 is a resist film deposited on the surface of this piezoelectric vibrator 4. As shown in FIG. To explain in more detail by giving specific numerical values, the diameter of the ferroelectric substrate 1 is 14 mm;
The thickness is 0.5 mm and its resonant frequency is 5.9583.
At 8 MHz, the resist film 6 has a molecular weight of 5×10
After applying polymethyl methacrylate to a film thickness of 5,000 mm, prebaking at 180° C. for 60 minutes is used. When the resist film 6 is applied to the surface of the piezoelectric vibrator 4 in this way, the resonant frequency of the vibrator 4 is 3.
．． It was confirmed that the frequency had decreased by 48KHz.

As shown in FIG. 1, the piezoelectric vibrator 4 having the resist film 6 coated on its surface is immersed in a developer 7 to develop the resist film 6 while monitoring the resonance frequency of the piezoelectric vibrator 4.

The developer 7 used here is ethyl cellosolve/isopropyl alcohol = 97.5
/2.5 (volume ratio), and the developing temperature was 22°C. The changes in the resonant frequency of the piezoelectric vibrator 4 when this IJl image processing was carried out using an unused developer and when using a used developer that had been left for 3 days after being used for development were evaluated in the third example. As shown in the figure. Curve A is for an unused developer, and the resonant frequency of the piezoelectric resonator reaches the resist film 6 after being immersed in the developer for about 10 minutes.
It has returned to its previous state, and also the song #! B shows the case of a used developer, and the resonant frequency has not returned to its original state even after 15 minutes have passed after immersion. This shows that the frequency change is large in comparison, and the used developing solution shows that the developing speed is slow, that is, the developing ability is reduced.

The piezoelectric resonator 4 coated with the resist film 6 is then exposed to a developer 7.
The deterioration state of the resist developer, that is, the lifespan of the developer can be determined by immersing the resist developer in water and monitoring the change in its resonance frequency.

(g) Effects of the Invention As is clear from the above description, the present invention involves immersing a piezoelectric vibrator coated with a resist film in a resist developer to be inspected, and monitoring the frequency change of the piezoelectric vibrator. Since it is configured to know the status of the resist developer by
The deterioration status and lifespan of the developer can be monitored prior to implementation of the development operation, and the present invention brings great benefits to this field.

[Brief explanation of drawings]

Fig. 1 is a conceptual diagram showing the configuration of the resist developer inspection device of the present invention, Fig. 2 is an enlarged side view of the main parts thereof, Fig. 3 is a curve diagram showing the inspection status by the inventive device, and Fig. 4 is a resist developer test device of the present invention. FIG. 3 is a cross-sectional view for explaining the pattern formation situation. 1... Ferroelectric substrate, 4... Piezoelectric vibration f, 5...
Oscillation circuit, 6...resist film, 7. developer.

Claims (1)

[Claims] (1) A piezoelectric vibrator configured by providing electrodes on a ferroelectric substrate is provided, and a resist film developed with a resist liquid to be inspected is deposited on the surface of the vibrator, and this resist film is deposited. A resist developer characterized in that the resist developer to be inspected is inspected by immersing a piezoelectric vibrator in the resist developer to be inspected and detecting the state of development of a resist film by the developer based on a change in the resonance frequency of the vibrator. Inspection equipment.