Dai Nippon Printing Co., Ltd.

Yasutaka Morikawa

Katsuya Hayano

Hiroshi Mohri

Takaharu Nagai

Nobuhito Toyama

Takashi Adachi

Kenji Noguchi

Takashi Tominaga

Yoichi Takahashi

Junji Fujikawa

Toshifumi Yokoyama

Yoshinori Kinase

Toshiaki Motonaga

Hiro-o Nakagawa

Yuichi Inazuki

Hideyoshi Takamizawa

Kei Mesuda

Yasuhisa Kitahata

Takanori Sutou

The present invention provides a halftone mask comprising an assist pattern and a manufacturing method of the halftone mask, which uses an ArF excimer laser as an exposing source, is used for a projection exposure by an off axis illumination, does not resolve the as pattern while keeping the focal depth magnification effect as the assist pattern, and may form a transferred image having high contrast of a main pattern. A photomask is a photomask comprising the main pattern which is transferred to a transfer-target surface by the projection exposure and the assist pattern which is formed nearby the main pattern and not transferred, characterized in that the main pattern and the assist pattern are each constituted from a semi-transparent film made of the same material, a retardation of 180&#xb0; is generated between the light transmitting through the main pattern and the light transmitting through a transparent region of a transparent substrate, and a predetermined retardation within the scope of 70&#xb0; to 115&#xb0; is generated between the light transmitting through the assist pattern and the light transmitting through the transparent region of the transparent substrate.

Photomask and methods for manufacturing and correcting photomask

The present invention provides a halftone mask comprising an assist pattern and a manufacturing method of the halftone mask, which uses an ArF excimer laser as an exposing source, is used for a projection exposure by an off axis illumination, does not resolve the assist pattern while keeping the focal depth magnification effect as the assist pattern, and may form a transferred image having high contrast of a main pattern. A photomask is a photomask comprising the main pattern which is transferred to a transfer-target surface by the projection exposure and the assist pattern which is formed nearby the main pattern and not transferred, characterized in that the main pattern and the assist pattern are each constituted from a semi-transparent film made of the same material, a retardation of 180&#xb0; is generated between the light transmitting through the main pattern and the light transmitting through a transparent region of a transparent substrate, and a predetermined retardation within the scope of 70&#xb0; to 115&#xb0; is generated between the light transmitting through the assist pattern and the light transmitting through the transparent region of the transparent substrate.

A photomask which improves the imaging performance that the photomask has and forming a good micro image on a wafer in photolithography with a half pitch of 60 nm or less. Provided is a photomask used for photolithography using an ArF excimer laser as an exposing source for immersion exposure by quadrupole-polarized illumination with a high-NA lens. The photomask includes a mask pattern of a light shielding film or semi-transparent film on a transparent substrate, and further, given that a thickness of the light shielding film or semi-transparent film is 't' nm, a refractive index is 'n', an extinction factor is &#x201c;k&#x201d;, and a bias of a space part of the mask pattern is &#x201c;d&#x201d; nm, when &#x201c;t&#x201d;, &#x201c;d&#x201d;, &#x201c;n&#x201d; and &#x201c;k&#x201d; are adjusted and the photomask is used for the photolithography, optical image contrast takes a value exceeding 0.580.

Photomask

A planar pattern (), having a plurality of apertures of the same size (Wx&#xd7;Wy), is determined by a two-dimensional layout determination tool (), and a three-dimensional structure, having a depth d and an undercut amount Uc for making the phase of the transmitted light be shifted by 180 degrees with every even-numbered aperture, is determined by a three-dimensional structure determination tool (). Simulation of transmitted light is executed for a structural body having the planar pattern () and the three-dimensional structure () by a three-dimensional simulator () to determine the light intensity deviation D of transmitted light for an odd-numbered aperture without a trench and an even-numbered aperture with a trench. At a two-dimensional simulator (), simulations using a two-dimensional model prepared based on this deviation D are performed to determine a correction amount &#x3b4; for making the deviation D zero and obtain a new planar pattern (). The work load spent on designing a trench-type, Levenson-type phase shift mask can be lightened and the working time for the designing process can be shortened.

Designing method and device for phase shift mask

A photomask is produced which enables the simplification of the steps of lithography. A photomask is provided with shielding patterns made of shielding metallic thin film on a transparent substrate, wherein the photomask further comprises translucent patterns mainly including tantalum of materials selected from tantalum silicide, tantalum oxide, tantalum nitride or mixture thereof.

Growing community of inventors

Tokyo-to, Japan

Yasutaka Morikawa