The deposition characteristics of carbon film on EUV mask surface, the impact of carbon deposition on lithography performance, and cleaning of deposited carbon film on EUV mask are studied. The density of the carbon film was found to be nearly half of that of graphite by X-ray reflectivity measurement. The impact of carbon deposition on the lithography performance was simulated by SOLID-EUV. The CD variation by carbon deposition on the mask depends on the deposition profile on the absorber pattern. Intentionally created contaminated masks were treated by a cleaning process using atomic hydrogen. The cleaning efficiency and durability of film materials are discussed.

Recently, there has been a demand for lead (Pb)-free solders for use in the electronics industry. However, this poses a challenge in their practical applications because the main component of typical Pb-free solders is tin (Sn) and therefore these solders are prone to oxidize easily. In this paper, we propose a novel technique for the reduction of oxides of the powder which is the raw material of Pb-free solders, and which has Sn as its main component using NH 3 decomposed species generated using a hot-wire (HW) method. It is confirmed that the tin oxide can be reduced by this treatment and the re-oxidation of the solder is also suppressed. Moreover, it is also confirmed that this treatment is effective in controlling the particle size of the Pb-free solder. Further, we clarify that the activation energy of the reduction of the tin oxide is almost zero by this process is almost zero, which indicates that the temperature dependence of the reduction is low.

A new high-density optical disk system has been investigated experimentally. In this system, the optical disk has grooves with a V-shaped cross-sectional configuration. The V-shaped grooves are spaced bottom to bottom by the presently used track pitch, and all walls of the grooves are capable of storing information. The cross talk from information on an adjacent wall has been determined to be almost equal to that of the presently used optical disk, and the new system is verified to double the information density of the optical disk.