Surface Chemistry of Ruthenium Dioxide in Heterogeneous Catalysis and Electrocatalysis: From Fundamental to Applied Research

Lithography is a field in which advances proceed at a swift pace. This book was written to address several needs, and the revisions for the second edition were made with those original objectives in mind. Many new topics have been included in this text commensurate with the progress that has taken place during the past few years, and several subjects are discussed in more detail. This book is intended to serve as an introduction to the science of microlithography for people who are unfamiliar with the subject. Topics directly related to the tools used to manufacture integrated circuits are addressed in depth, including such topics as overlay, the stages of exposure, tools, and light sources. This text also contains numerous references for students who want to investigate particular topics in more detail, and they provide the experienced lithographer with lists of references by topic as well. It is expected that the reader of this book will have a foundation in basic physics and chemistry. No topics will require knowledge of mathematics beyond elementary calculus.

Principles of Lithography

Extreme ultraviolet lithography (EUVL) was thoroughly reviewed over a broad range of topics, including history, tools, source, metrology, condenser and projection optics, resists, and masks. Since 1988, many studies on EUVL have been conducted in North America, Europe, and Japan, through state sponsored programs and industrial consortiums. To date, no “show stopper” has been identified, but challenges are present in almost all aspects of EUVL technology. Commercial alpha lithography step-and-scan tools are installed with full-field capability; however, EUVL power at intermediate focus (IF) has not yet met volume manufacturing requirements. Compared with the target of 180W IF power, current tools can supply only approximately 55–62W. EUV IF power has been improved gradually from xenon- to tin-discharge-produced plasma or laser-produced plasma. EUVL resist has improved significantly in the last few years, with 25nm 1:1 line/space resolution being produced with approximately 2.7nm (3σ) line edge roughness. A...

Extreme ultraviolet lithography: A review

A method for fabricating a semiconductor device, in which a lifting phenomenon can be prevented from occurring in forming an amorphous carbon film on an etched layer having tensile stress. According to the invention, since a compression stress on the etched layer or the amorphous carbon film can be reduced or a compression stress film is formed between the etched layer or the amorphous carbon film to prevent a lifting phenomenon from occurring and thus another pattern can be formed to fabricate a highly integrated semiconductor device.

Method for Fabricating Semiconductor Device

A glass substrate-holding tool, adapted to be employed during the production of a reflective mask blank for EUV lithography (EUVL), includes an electrostatic chuck and a supporting member. The chuck attracts a rear surface of a glass substrate in a non-contact manner by electrostatic attractive force. The supporting member partly supports the rear surface. An area ratio of a projected area of an active surface of the chuck for providing the electrostatic force to an area of a quality-guaranteed region of the rear surface is from 0.5 to 1.0. The active surface is apart from the rear surface by more than 20 μm. The supporting member is configured to support only a region including at least two of four sides defining an outer portion outside the quality-guaranteed region.

Glass substrate-holding tool and method for producing an EUV mask blank by employing the same

A reflection type mask blank comprising a substrate (11), and, sequentially formed thereon, a reflection layer (12) for reflecting an exposure light in a short-wave region including an extreme ultraviolet region and an absorber layer (16) for absorbing an exposure light. The absorber layer (16) has a structure of at least two layers consisting of as a lower layer an exposure light absorbing layer (14) composed of an absorber of an exposure light in a short-wave region including an extreme ultraviolet region, and as an upper layer a low-reflectance layer (15) composed of an absorber of an inspection light used for mask pattern inspection. The upper layer consists of a material containing tantalum (Ta), boron (B) and nitrogen (N), B content being 5 at%-30 at%, a composition ratio between Ta and N (Ta:N) being 8:1 to 2:7. Alternatively, the reflection type mask blank may comprise a substrate, and, sequentially formed thereon, a multi-layer reflection film and an absorber layer, wherein the absorber layer consists of a material containing tantalum (Ta), boron (B) and nitrogen (N), B content being 5 at%-25 at%, a composition ratio between Ta and N (Ta:N) being 8:1 to 2:7.

Reflection type mask blank and reflection type mask and production methods for them

PROBLEM TO BE SOLVED: To provide a reflective mask and a mask blank which enable correct and prompt inspection of mask patterns. SOLUTION: The mask blank consists of a substrate 11, a reflector layer 12 for reflecting exposure light of short wavelength including extreme ultraviolet wavelength, a buffer layer 13 for protecting the reflector layer 12 in forming mask patterns, and an absorber layer 16 for absorbing exposure light. These elements are stacked in this order on the substrate 11. The absorber layer 16 has a two-layer structure which is provided with an absorber layer 14 as a lower layer consisting of an absorber for absorbing exposure light of short wavelength including extreme ultraviolet wavelength, and a low reflector layer 15 as an upper layer consisting of an absorber for absorbing inspection light for use in mask pattern inspection. The reflective mask 2 is obtained by forming the absorber layer 16 of the mask blank into patterns. COPYRIGHT: (C)2004,JPO

Reflective mask blank, reflective mask, method for manufacturing the same and method for manufacturing semiconductor

6-inch EUV masks consisting of Mo/Si multilayers and patterned CrX buffer and TaBN absorber layers have recently been developed and evaluated. Mo/Si multilayers with a relatively high EUV reflectivity of 66 percent and an excellent uniformity were obtained on the polished ULE substrates by an ion beam sputtering method. The multilayers showed high durability to the acid abased cleaning and baking at 150 degrees C used in the conventional mask-making process. The Cr based film was optimized as a repair buffer to obtain a high reflectivity of 52 percent at 257 nm and low stress within 100 MPa. TaBN absorbers with a low reflectivity were obtained by optimizing the film compositions, which resulted in a high image contrast to the multilayer for DUV inspection. An EUV contrast level of 99 percent was achieved for a thinner, 100-nm thick absorber stack. Using the optimized mask process, EUV mask with patterns of 180-nm width were successfully obtained, without a significant drop in EUV reflectivity.

Process development of 6-in EUV mask with TaBN absorber

In a reflection type mask blank for EUV exposure with a substrate, a multilayer film is formed on the substrate so as to reflect an EUV light ray. A light absorber layer is formed on the multilayer film so as to absorb the EUV light ray. The multilayer film has flatness with respect to a surface thereof, and the flatness is 100 nm or less.

Substrate with multilayer film, reflection type mask blank for exposure, reflection type mask for exposure and production method thereof as well as production method of semiconductor device

PROBLEM TO BE SOLVED: To provide a reflection mask blank which is furnished with a protection film on a multilayer reflecting film, wherein the protection film provides excellent capability of protecting an absorber film or the like formed on the multilayer reflecting film in forming a pattern, does not cause degradation of the reflectivity of the multilayer reflecting film, and provides a satisfactory oxidation-inhibiting effect for the multilayer reflecting film, and to provide a reflection mask using the mask blank. SOLUTION: The reflection mask blank 10 comprises a substrate 1, and a multilayer reflecting film 2 that reflects exposure light, a protection film on the multilayer reflecting film 2, a buffer layer 3, and an absorber film 4 that absorbs the exposure light, sequentially formed on the substrate. The protection film is formed of a ruthenium compound containing ruthenium (Ru) and at least one kind selected from molybdenum (Mo), niobium (Nb), zirconium (Zr), yttrium (Y), boron (B), titanium (Ti), and lanthanum (La). A reflection enhancing film composed of Ru may be formed on the protection film surface. The reflection mask 20 is provided by forming a transfer pattern on the absorber film of the reflection mask blank. COPYRIGHT: (C)2005,JPO&NCIPI

Morio Hosoya

Papers

Reflection type mask blank and reflection type mask and production methods for them

Reflective mask blank, reflective mask, method for manufacturing the same and method for manufacturing semiconductor

Process development of 6-in EUV mask with TaBN absorber

Substrate with multilayer film, reflection type mask blank for exposure, reflection type mask for exposure and production method thereof as well as production method of semiconductor device

Reflection mask blank, reflection mask, and method of manufacturing semiconductor device