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In this paper, a near-field photolithographic method which can realize ultra high resolution beyond the diffraction limit of light is described. Evanescent light generated on a transparent mold with a micro-relief illuminated on the condition of total internal reflection is used to expose a photoresist in contact with the mold. The plastic replica mold is flexible to eliminate the difficulty of close contact with the photoresist, and the replica mold damaged by the contact with the photoresist is disposable to maintain a high yield rate. We printed sub-100 nm features on a commercially available photoresist using 442-nm-wavelength light.

In iron-related deep levels in n-type silicon, the introduced concentration of Ec-0.21 eV(B) and Ec-0.41 eV(C) levels decrease with increasing the diffusion time at 1160°C, indicating that the formation process includes the conversion process into other types of complexes. The concentration of the C level decays exponentially with the duration of isothermal annealing up to 200°C, the time constant activation energy being 0.65 eV. The results indicate that the observed defects are due to the intermediate states in consecutive reactions of iron-related complex formation.

Isothermal capacitance transient spectroscopy (ICTS) has been used to measure majority-carrier capture cross section of nickel centers in silicon. Capture cross sections obtained are temperature-independent with values of 3.2×10-17cm2for electron capture at the nickel acceptor center in n-type silicon and 1.8×10-16cm2for hole capture at the nickel donor center in p-type silicon. These capture cross sections are associated with the neutral capture of the majority carriers at the amphoteric nickel centers.

Electrically active iron-related defects in Czochralski (CZ) n-type silicon have been studied using deep level transient spectroscopy (DLTS) and the Hall effect. Iron-related defects observed in CZ n-type silicon are identical to those in floating zoned (FZ) n-type silicon. These observed defects can be related to complexes, including iron atoms.

Diffusion and electrical properties of iron-related defects in n-type silicon are studied in Czochralski (CZ) and floating zone (FZ) silicon by means of deep level transient spectroscopy and the Hall effect. Introduction and annealing behaviors of electrically active iron-related defects reveal that these defects can be related to complexes containing interstitial iron atoms. The formation of iron-related defects at high temperatures includes defect reaction processes such that the observed complexes could be due to the intermediate states in consecutive reactions of iron-related complex formation. The electrically active complexes are independent of phosphorus or oxygen atoms. The iron-related defects observed in CZ silicon are identical to those observed in FZ silicon.

Iron introduces a donor level at about Ec-0.4 eV in n-type silicon. In this work, the electrical properties of this donor state have been studied by deep-level transient spectroscopy (DLTS). It is found, by resolving the overlapping DLTS peaks obtained after room temperature annealing, that the donor decomposes into several other states. Isothermal annealing of samples containing different amounts of phosphorus show that phosphorus has no significant effect on the annealing decay constant of the donor, indicating that phosphorus atoms do not take part in the annealing decay of the donor. A Poole-Frenkel field emission effect is observed in the donor level as expected for donors in n-type silicon.