Mitsubishi Denki Kabushiki Kaisha

Koji Kise

Sunao Aya

Hideki Yabe

Kenji Marumoto

Hiroshi Watanabe

Hiroaki Sumitani

Kaeko Kitamura

Takashi Hifumi

Takaaki Murakami

Kenji Itoga

Kei Sasaki

Shigeto Ami

In fabricating an X-ray mask, a chromium oxide film serving as an etching stopper is formed on a diamond film serving as an X-ray transmitter. Then, a diamond layer serving as a first X-ray absorber is formed on the chromium oxide film. Thereafter, a tungsten layer serving as a second X-ray absorber is formed on the diamond layer. Consequently, the diamond layer and the tungsten layer form an X-ray absorber having a laminated structure. When the X-ray absorber has a laminated structure including substances having different compositions, the transmittance and the phase shift quantity of the overall X-ray absorber can be readily adjusted. Thus, a method of fabricating an X-ray mask providing improved resolution of the pattern of a semiconductor device or the like is obtained.

Method of fabricating X-ray mask and method of fabricating semiconductor device using the X-ray mask

A resist is on a substrate with a lower layer film between the resist and the substrate. The lower layer film includes chemical elements and the element absorbing the largest amount of x-rays is carbon. The thickness of the lower layer film is determined by considering the influences of secondary electrons from the substrate and the carbon of the lower layer film. The resist includes chlorine, or a similar element, having a specific absorption edge. Under such conditions, the average wavelength of x-rays absorbed in the resist is in a prescribed range. In this way, in x-ray exposure, blur caused by secondary electrons is suppressed using a wavelength region of relatively shorter wavelengths.

X-ray exposure method

An X-ray absorber is deposited on a membrane. A stress adjust step is applied so that the average film stress of the X-ray absorber is 0. After patterning the X-ray absorber, the position accuracy of the pattern is measured. Then, a stress adjust process is applied to the patterned X-ray mask. Accordingly, a stress adjustment method is used to acquire an X-ray mask that has no pattern position offset of the X-ray absorber.

Stress adjustment method of X-ray mask

X-ray mask provided with an alignment mark and method of manufacturing the same

An X-ray mask including a transfer pattern having high accuracy is obtained. In a method of manufacturing the X-ray mask, an X-ray absorber film preventing transmission of an X-ray is formed on a substrate. A resist film is formed on the X-ray absorber film. The substrate is placed on a movable member. Steps of moving the movable member and irradiating the resist film with an energy beam are repeated for carrying out a drawing step of drawing a pattern on the resist film. Between the step of placing the substrate on the movable member and the drawing step, a step of holding a mask member including the resist film, the X-ray absorber film and the substrate to be in a state substantially identical to thermal equilibrium in the drawing step is carried out.

X-ray mask and method of manufacturing the same

The X-ray mask manufactured according to the present invention can solve a problem that the thin film stress of the X-ray absorber cannot be made to be zero although the mean thin film stress throughout the X-ray absorber can be made to be zero. The thin film stress distribution over the X-ray absorber 4 after the X-ray absorber 4 has been formed on a silicon substrate 1 is measured, and then inputs of electric power to heaters 9a, 9b and 9c of a hot plate 8 are changed so as to heat the X-ray absorber 4 to temperatures according to a specified temperature distribution with which the thin film stress throughout the X-ray absorber can be made to be zero.

Method of manufacturing X-ray mask and heating apparatus

A method of making a X-ray mask including: a step of forming a X-ray absorber above a substrate; a step of controlling a stress of the X-ray absorber by a predetermined condition; and wherein the predetermined condition for controlling the stress of the X-ray absorber formed above the substrate is determined by a measured value of a stress of a X-ray absorber formed on a monitor substrate.

Growing community of inventors

Hyogo, Japan

Koji Kise