JPS63266825A - Organic matter removal method - Google Patents

Abstract

PURPOSE:To reduce power consumption and to prevent sodium or the like from diffusing by irradiating a substrate with an ultraviolet ray which contains specific wavelength in an atmosphere containing oxygen, including specific amount of ozone, and specifying the substrate temperature and the illuminance of the ultraviolet ray. CONSTITUTION:An ultraviolet lamp 1 uses a low-pressure mercury vapor discharge lamp, and a substrate 4 is heated by a heater mounted at a substrate holder 5. In this case, the illuminance of the ultraviolet ray is 50mW/cm<2> or more on the substrate surface. The lamp 1 irradiates the ray which contains 185, 194 and 254nm of wavelengths on the surface of the substrate 4, and the heater operates to heat the substrate 4 to 100-200 deg.C. The ozone concentration of oxygen gas 3 containing ozone is 3 vol.% or more. The substrate 4 is coated with organic photoresist at the thickness of 10000Angstrom on a silicon wafer. As a result, power consumption is reduced, and the diffusion of sodium to the substrate is alleviated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for removing organic matter, and particularly to a method for removing organic matter that does not damage a substrate and has a high M organic matter removal rate.

[Conventional technology]

In the conventional method, as described in Japanese Patent Publication No. 58-15939, the entire substrate was heated using the radiant energy of an ultraviolet lamp to remove organic substances such as organic photoresists. Also, the temperature used was around 250C.

[Problem that the invention seeks to solve]

The conventional technology described above uses an ultraviolet door lamp for heating, so a doll lamp of 900 watts is used, and a large
It was consuming a lot of energy. Furthermore, since the substrate temperature was raised to around 1250° C., for example, when the organic photoresist is completely removed, the sodium in the resist may diffuse into the substrate and have an adverse effect.

As described above, the above-mentioned points have not been taken into consideration in the prior art, and therefore, the present invention aims to provide an organic matter removal method that solves these points.

[Means for solving problems]

The lamp uses a low-pressure mercury vapor discharge lamp to effectively irradiate ultraviolet light of 180 to 300 nm.

The substrate is heated by a heater installed in the substrate holder. In this case, the ultraviolet irradiance is set to 50 mw/cm 2 or more on the substrate surface. or.

The substrate temperature is in the range of 100 to 2001:'. This achieves the aforementioned objectives.

[Effect]

The lamps are 185 nm and 194 nm on the substrate surface.

The entire substrate is irradiated with ultraviolet light including a wavelength of 254 nm, and the heater is operated to heat the substrate to 100 to 200C.

That is, heating is performed by an appropriate method (in the present invention, heating by a heater provided in the holder), and serves to avoid irrational heating by an ultraviolet lamp.

〔Example〕

The lamp was a 140 watt low pressure mercury lamp, lamp current: IA, and filled gas: Ne-Ar mixed gas.

The heater was embedded in the holder and had a power of 300 watts.

The ozone concentration was set to 5 volumes.

The distance between the lamp and the substrate was set to 1, and the ultraviolet irradiance on the surface of the substrate was 60 mW/cm 2 . Also, the substrate temperature is 200C
And so.

The substrate used was a silicon wafer coated with an organic photoresist to a thickness of 10,000 yen.

As a result, the power consumption was just under 500 watts, and the resist was removed in 1.3 minutes. Diffusion of sodium into the base was very slight and caused no problems in practical use.

When the ozone concentration is low or when the ultraviolet illumination is low, the resist removal time becomes long, making it impractical. Furthermore, when the substrate temperature decreases, the diffusion of sodium, etc. in the resist increases, resulting in a decrease in performance yield.

〔Effect of the invention〕

According to the present invention, power consumption can be reduced and the phenomenon of diffusion of sodium and the like can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the method of the present invention. 1... Ultraviolet lamp, 2... Nozzle, 3... Oxygen gas containing ozone, 4... Substrate, 5... Holder and heater. 1st mouth, 9 outside - Izumi lamp 2 nosle 3 on's luxury and just electric power, be, 4 base 5, JLy and heater

Claims (1)

[Claims] 1. In an oxygen-containing atmosphere containing at least 3% ozone by volume, irradiate ultraviolet rays containing wavelengths of 185 nm, 194 nm, and 254 nm, and lower the substrate temperature to 10
A method for removing organic substances, characterized in that the temperature is raised to 0 to 200°C, and the illuminance of the ultraviolet rays is at least 50 mW/cm^2 on the surface of the substrate.