JPS6158235A - Resist processing method - Google Patents

Abstract

PURPOSE:To contrive stabilization of a resist film or a resist pattern by a method wherein the material of low molecular weight having a crosslinking radical or one containing a high molecular weight radical catching agent is used as an additive. CONSTITUTION:A wafer, wherein an Al alloy film having a positive type photoresist pattern is provided, is fixed on the substrate which is maintained at the prescribed temperature, and far ultraviolet rays are made to irradiate on the whole surface. A crosslinking reaction is generated on the surface layer of the resist pattern by the above-mentioned treatment. Then, after the wafer is washed, it is retained on the supporting stand which is maintained at the prescribed temperature, and ultraviolet rays and far ultraviolet rays are made to irradiate on the whole surface by running an alternate current on the coil provided close to the reverse side of the wafer while it is being worked as an electromagnet. Subsequently, an anisotropic dry etching treatment is performed on the Al alloy film located on the wafer surface using the resist pattern as a mask. According to this method, as an additive infiltrates into a porous film region and fixed in a coupled manner, the deformation and the resisting property for dry etching of the wafer can be improved.

Description

[Detailed description of the invention] [Technical field of the invention]
For example, it relates to an improved method that improves shape stability.

[Technical Background of the Invention] In recent years, with the miniaturization of lithography technology, the requirements for rests or resist patterns have reached a more advanced stage, and various functions have accordingly been required.

In particular, in the dry etching technology adopted for the purpose of high-precision, high-resolution processing, the etching species with high energy reacts with the resist surface, and due to the heat generated during etching, the resist is often Deformation and lack of dry etching resistance have been pointed out.

To deal with this type of resist deformation and lack of dry elatin resistance, resist materials have been carefully studied.On the other hand, many attempts have been proposed to solve the problems by improving processing methods. ing.

For example, conventional methods have improved the problem of bagginess by irradiating UV light, including deep ultraviolet light.

Furthermore, there is a method that has conventionally achieved the effect of preventing deformation of a resist pattern due to heat flow, etc. by synchronizing the effect of a magnetic field and irradiation with a xenon lamp and pulsing it.

In the former method (22), in the case of resists that are prone to heat flow, treatment for more than 5 minutes is not sufficient, although the effect is produced, and a gas containing fluorine is applied using the treated resist pattern as a mask. When a dry etching process was carried out on a silicon metallized film using the resist pattern, the resist pattern was significantly deformed and wrinkling occurred on the surface layer of the pattern.This result indicates that the absorption of deep ultraviolet light is limited to the resist (J/-). Therefore, the effect of curing the resist by far ultraviolet light is only for the professional class1;
This can be explained by the fact that fluidity remains inside the resist.

In addition, although the latter method does cause hardening, the processing time is 10
It has been reported that the resist thickness (d) decreases rapidly when the time exceeds seconds.

That is, in the prior art (2), there were problems in that the double film thickness was reduced, the effect was limited to only the surface layer (2), and curing was insufficient.

[Purpose of the invention]

The present invention has been made to address the problems of the prior art described above, and its purpose is to resist! Another object of the present invention is to provide a processing method that stabilizes the film quality and shape of a resist pattern, eliminates deformation during microfabrication processing, etc. performed using a resist film or resist pattern, and improves resistance.

[Summary of the invention]

In the present invention, a substrate having a resist film or a resist pattern is irradiated with UV light or ultraviolet light.

A method of processing using a processing device (two devices) having at least three functions: substrate temperature control, magnetic field generation, and additive supply to the substrate surface, and each function being carried out sequentially or simultaneously; The agent consists of a solution of a material selected for the purpose of achieving resist stabilization by penetrating the resist material and reacting with the resist material thermally or optically, and has at least a low molecular weight and a crosslinking group. It is characterized by containing a material or a high molecular weight radical scavenger.

〔Effect of the invention〕

By applying the present invention, a resist film or a resist pattern is stabilized, and a resist pattern is formed that is suitable for microfabrication processing, has little deformation, does not cause film roughening, has excellent etching resistance, and has excellent masking effects.

[Embodiments of the invention]

The processing steps of one embodiment of the present invention will be explained below.

First, patterns are repeatedly formed on a silicon wafer for the purpose of manufacturing semiconductor devices, and then the entire surface is coated to form wiring.
Two alloy films were provided with a thickness of approximately 0.8 μm.

Next, a positive photoresist pattern was formed using a normal process (2).The wafer was then fixed on a substrate held at about 100 °C, and the entire surface was irradiated with deep ultraviolet light for 3 minutes. The atmosphere was purged with N2. This treatment caused a crosslinking reaction on the surface layer of the resist pattern. The wafer was then washed with polyvinylphenol oligomer DPPH (radical scavenger) and ethyl alcohol containing 20 g of anionic surfactant added. After soaking in an organic alkaline aqueous solution, washing with water, and drying, hold it on a support stand held at 100C (C) and apply an alternating current to a coil placed close to the back side, making it act as an electromagnet. Irradiation with ultraviolet light and deep ultraviolet light was performed. After processing for 1 minute, the AJ alloy film was subjected to anisotropic dry etching using a mixed gas of C (J, and 0.0) using the resist pattern as a mask.

The selectivity ratio of the resist, which used to be about 3 to 4, is now
When the present invention (2) was subjected to such treatment (2), the improvement was about 5 to 7.

In other words, the present invention (second part) first maintains the shape of the resist through a crosslinking reaction using deep ultraviolet light, and then fixes the additive by photoreacting with the resist, thereby compensating for the lack of dry etching resistance of the resist. In addition, in order to achieve curing of the resist, conventionally, when the crosslinking reaction is caused by light irradiation to achieve sufficient curing, porosity is created due to the decomposition reaction that occurs as a side effect. In other words, the additive penetrates into the porous area and is bonded and fixed, making the resist denser and more resistant to deformation and dry etching.

In addition, the magnetic field contributes to stabilizing the three-dimensional structure of the resist polymer material, and is particularly effective when photoexcited or thermally (bi-polymer is excited), which simultaneously causes excitation of the polymer. It was more effective.

That is, stabilization of the resist can be achieved simply by combining the effects of photoreaction, magnetic field, and heat. Map, the immersion and fixing of the additive should be repeated (more effects were obtained from the second step).

Claims (1)

[Claims] A resist film or a substrate having a resist pattern is placed on a processing device having at least three functions: deep ultraviolet light irradiation, ultraviolet light irradiation, substrate temperature control, magnetic field generation, and additive supply to the substrate surface. A processing method in which the additives are used sequentially or simultaneously, and the additives are selected for the purpose of stabilizing the resist by penetrating through the resist surface and reacting with the resist material thermally or by light. 1. A resist processing method comprising a solution of a material having a low molecular weight and at least a material having a crosslinking group or a high molecular weight radical scavenger.