There is provided a light emitting device in which low power consumption can be realized even in the case of a large screen. The surface of a source signal line or a power supply line in a pixel portion is plated to reduce a resistance of a wiring. The source signal line in the pixel portion is manufactured by a step different from a source signal line in a driver circuit portion. The power supply line in the pixel portion is manufactured by a step different from a power supply line led on a substrate. A terminal is similarly plated to made the resistance reduction. It is desirable that a wiring before plating is made of the same material as a gate electrode and the surface of the wiring is plated to form the source signal line or the power supply line.

Light emitting device and method of manufacturing the same

The phase-shifting mask consists of a normal transmission mask that has been coated with a transparent layer patterned to ensure that the optical phases of nearest apertures are opposite. Destructive interference between waves from adjacent apertures cancels some diffraction effects and increases the spatial resolution with which such patterns can be projected. A simple theory predicts a near doubling of resolution for illumination with partial incoherence σ < 0.3, and substantial improvements in resolution for σ < 0.7. Initial results obtained with a phase-shifting mask patterned with typical device structures by electron-beam lithography and exposed using a Mann 4800 10× tool reveals a 40-percent increase in usuable resolution with some structures printed at a resolution of 1000 lines/mm. Phase-shifting mask structures can be used to facilitate proximity printing with larger gaps between mask and wafer. Theory indicates that the increase in resolution is accompanied by a minimal decrease in depth of focus. Thus the phase-shifting mask may be the most desirable device for enhancing optical lithography resolution in the VLSI/VHSIC era.

Improving resolution in photolithography with a phase-shifting mask

Process gas discharged from a bypass pipe to a gas exhaust system can be prevented from diffusing back to the inside of a process chamber without having to install a dedicated vacuum pump at the downstream side of the bypass pipe. The substrate processing apparatus includes a process chamber accommodating a substrate, a gas supply system supplying process gas from a process gas source to the process chamber for processing the substrate, a gas exhaust system configured to exhaust the process chamber, two or more vacuum pumps installed in series at the gas exhaust system, and a bypass pipe connected between the gas supply system and the gas exhaust system. The most upstream one of the vacuum pumps is a mechanical booster pump, and the bypass pipe is connected between the mechanical booster pump and the rest vacuum pumps located at a downstream side of the mechanical booster pump.

Substrate Processing Apparatus

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

Nanofabrication by electron beam lithography and its applications

PURPOSE:To provide the phase shift mask having high quality and the process for production thereof by decreasing processes at the time of producing the phase shift mask and to provide the exposure method using the phase shift mask CONSTITUTION:A second light transparent part 4 of the phase shift mask 200 is composed of molybdenum silicide oxynitride or molybdenum silicide oxide 4, of which the phase difference attains 180 deg and transmittance is 5 to 40% A molybdenum silicide oxynitricle film or molybdenum silicide oxide film is formed by using a sputtering method in the production stage for the second light transparent part 4 As a result, the second light transparent part is formed by using the conventional sputtering device and since the etching stage of the phase shifter parts is just once, the probability of generating defects and errors in the production stage is lowered

Phase shift mask and its production and exposure method using the phase shift mask

A phase-shifting photomask blank has a transparent substrate, a phase-shifting film deposited on the transparent substrate, the phase-shifting film including a transversely central composition which results in a reduced rate of side etching, and a patterned photoresist film masking the phase-shifting film. When the phase-shifting film is dry-etched through the patterned photoresist film into a desired circuit pattern, transversely different rates of side etching of the phase-shifting film are substantially equalized due to the reduced rate of side etching resulting from the transversely central composition. The circuit pattern includes openings defined by removal of the phase-shifting film and shifters left between the openings. The shifters have respective side surfaces free of steps and extending substantially perpendicularly from the transparent substrate. If the phase-shifting film comprises a film of molybdenum silicide oxide nitride deposited by sputtering, then the proportion of a nitrogen mono oxide gas in a sputtering gas is adjusted to control the transversely central composition of the phase-shifting film.

Phase-shifting photomask blank, phase-shifting photomask, and method of manufacturing them

To provide a photomask cleaning method which brings about a high effect of removing residual sulfuric acid or foreign objects and can remove foreign objects effectively without fluctuating the transmission or other properties of the light-shielding layer (MoSiON film) in a phase shift photomask. A method of cleaning a photomask which comprises a first step of cleaning the surface of a photomask used as a master in the photolithography step in the process for the production of semiconductor device with a hot mixture of sulfuric acid and hydrogen peroxide to decompose organic objects present thereon and remove metallic impurities, a second step of removing residual sulfuric acid from the surface of said photomask, a third step of removing foreign objects attached to the surface of said photomask, and a fourth step of drying said photomask which has finished with said first, second and third steps, characterized in that said second step involves the removal of residual sulfuric acid from the surface of said photomask with anodic water and said third step involves the removal of foreign objects with cathodic water.

Method and apparatus for cleaning photomask

The pattern size of the Logic devices and the Logic-embedded DRAM devices as well as the DRAM devices are reducing. For the photo mask accurate critical dimension (CD) and CD uniformity are needed. Therefore the Cr dry etching process has been studied. But it is well known that the CD loss is affected by pattern density. This phenomenon was called loading effect. This is a big issue to apply dry etching for advanced photo mask process such as 180 nm generation and later. For example, there was about 90 nm line width difference of a test mask (6' AR-chrome with ZEP-7000) processed by magnetically enhanced reactive ion etching (MERIE) using Cl2+O2 gas mixture. In general, it is known that adding another gas is helpful for etching rate uniformity in dry etching. Effect of H2, HCl and NH3 as the adding gas in Cl2+O2, was investigated using a MERIE system (MEPS-6025) for improving line width difference between clearfield and darkfield. It was found that an adding gas including H had some effect for reduction of the difference. H2 and HCl was effective, and reduction of the difference was about 90% to 67%. With this condition the Cr dry etching rate increased. Therefore the all problem of Cr dry etching was solved. Using this dry etching process, the photo masks are supplied for 180 nm generation Logic-embedded DRAM devices.

Advanced Cr dry etching process

PURPOSE: To provide a phase shift mask which satisfies optical characteristics and chemical resistance, has high pattern precision, and develops no pattern crack. CONSTITUTION: When phase shift films 10, 40 for shifting the phase of exposure light are formed, phase shift photomask blanks are formed with about the thickness directional center being set to a composition having a slow side etching speed S when the films are formed with a single composition, so that the difference in the side etching quantity differed in the thickness direction of the phase shift films 10, 40 is minimized, and when phase shift photomasks 35, 39 are formed by dry etching, the side surfaces of shifter parts 7, 17 are raised almost vertically from transparent bases 5, 15. The regulation of adding ratio of NO gas at sputtering suffices for the use of a molybdenum silicide oxide nitride film as the phase shift film.

Nobuyuki Yoshioka

Papers

Phase shift mask and its production and exposure method using the phase shift mask

Phase-shifting photomask blank, phase-shifting photomask, and method of manufacturing them

Method and apparatus for cleaning photomask

Advanced Cr dry etching process

Phase shift photomask blanks, phase shift photomask, and their manufacture