Formation of low defect density SiOx films for Josephson integrated circuits

Abstract

SiOx films deposited by evaporation under oxygen atmosphere were investigated to form low defect density insulating layers in Josephson integrated circuits. The defect density is high in SiOx films deposited under an oxygen pressure of less than 1.33×10−3 Pa, but it decreases greatly in films deposited under higher oxygen pressure. This can be explained by the presence or absence of elemental Si in the films. Elemental Si is present in films deposited under low oxygen pressure, but not in films deposited under higher oxygen pressure. The insulating characteristics of a SiOx film deposited under an oxygen pressure of 1.33×10−2 Pa are excellent.

Characterization of thin films of a-SiOx(1.1<x<2.0) prepared by reactive evaporation of SiO

“…For films with x < 1.65, the Si 2p spectra show some shoulder and structures, while for films with x 1.65 such a shoulder was not observed (figure 3). The peak positions of the Si 2p determined [1,[12][13][14]19] for individual samples of elemental Si and SiO 2 are indicated in figure 3. This suggests that such a shoulder may have a contribution that is coming from the presence of elemental Si in the samples with x < 1.65.…”

“…) where the R are the relative concentrations of the three components (since R Si 1+ is nearly zero), given in figure 5. The factor of 1 2 is included since each oxygen atom is shared by two Si atoms. The values of x fit thus obtained are compared with those obtained from the ratio of the intensities of the O 1s and Si 2p core level peaks (x) in table 1.…”

“…Thin films of semi-insulating silicon suboxides deposited by the well-known method of reactive evaporation of SiO in an O 2 ambient are frequently used in semiconductor surface passivation and can be deposited at relatively low process temperatures [1]. The low process temperatures during the preparation of semiconductor films are needed to reduce problems such as substrate warpage, dopant redistribution and defect generation and migration caused by high-temperature processing [2].…”

Silicon monoxide – a convenient precursor for large scale synthesis of near infrared emitting monodisperse silicon nanocrystals

“…Evidently, precursors with higher Si content may be advantageous for obtaining higher yields of ncSi. Indeed, silicon nanoclusters formed in silicon monoxide (SiO) films [16][17][18][19] and other silicon sub-oxide (SiO x , x < 2) films, [20][21][22][23] usually prepared via thermal, plasma, and laser deposition, have been of interest in optical physics for applications as protective layers 24,25 and in silicon based optoelectronics. 26 Notably, SiO is also commercially available as powders in bulk quantities having a structure and properties that appears to be different from thin films.…”

Lattice distortion in ion beam synthesized silicon nanocrystals in SiOx thin films

“…Silicon suboxide (SiO x ) is an interesting material due to its various industrial applications as protective layers, insulating layers, optical coatings and gas‐barrier layers 1–5, and in a wide range of fields in physical sciences 6, 7. Sometimes SiO x is even preferred over silicon dioxide for its electrical properties and as a precursor for the formation of silicon nanocrystals, which are the most promising candidates for silicon‐based optoelectronics in the near future 8.…”