Copper in silicon

Abstract

The presence of Cu atoms in /?-type Si is detected via their characteristic electric-field gradients measured at the radioactive acceptor ,ll In/ m Cd by the perturbed yy angular correlation technique. Cu forms pairs with acceptor atoms, thereby electrically passivating them, and is present as a contamination in Si wafers. Using the experimentally known Cu diffusion data and taking into account the effect of ion pairing, a new activation energy of 0.15 eV is deduced which is in accordance with the dissociation energy of 0.70 eV measured for Coulombic-bound acceptor-Cu pairs.

Titanium and copper in Si: Barriers for diffusion and interactions with hydrogen

“…24) implementation of unrest, ricted ab initio Hartree-Fock (UHF) theory. 2 Clusters of various sizes and characteristics were used to represent the Si crystalline environment.…”

The Potential of the Perturbed Angular Correlation Technique in Characterizing Semiconductors

“…In the past, PAC spectroscopy has been utilized to observe the dopant-defect/dopant interaction in various semiconductors, e.g., using 111 In/Cd probe atoms, In-defect/dopant pairs have been observed in Ge 11,12 and Si. [8][9][10][17][18][19]44 Recently, we have observed such pairs with 100 Pd/Rh probe atoms in highly doped Si, i.e., Pd-vacancy defect pair in highly doped n-Si 41 and Pd-B defect pair in highly doped p-Si. 42 The corresponding PAC spectra are shown in Fig.…”

“…15 Using 77 Br as probe, the metastable behavior of anion-site donors in an InAs lattice was observed 16 where the transition between the substitutional and a nonsubstitutional configuration could be detected. The presence of interstitial impurities such as transition metals, e.g., Cu in Si, 17 and hydrogen in Si 18,19 and III-V semiconductors 20 have also been identified with PAC technique. PAC technique has been successfully applied to measure the hyperfine interactions at surface sites on GaAs(111)B and InAs(111)B reconstructed surfaces using 111…”

“…This sensitivity is advantageous for discriminating the presence of intrinsic and extrinsic defects in semiconductors, which is in general a basic problem in defect studies. Extensive PAC data are available on such measurements in semiconductors, [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] which can be summarized as follows:…”

Lattice Location and Stability of Ion Implanted Cu in Si

“…From the viewpoint of fundamental semiconductor physics this is due to the variety of physical phenomena which are associated with Cu in semiconductors. Positively charged Cu 1 is the fastest interstitial diffuser in Si, with a migration energy of only 0.18 eV [2,3]. At elevated temperatures the intrinsic solubility of Cu is the highest among all transition metals (at 1100 ± C, e.g., 9 3 10 17 cm 23 ) [4,5]; the solubility at room temperature is not known but must be very small (0.013 cm 23 extrapolated from high temperatures).…”