Stacking Faults In Silicon Research Articles

Polytypic quantum wells in Si and Ge: impact of 2D hexagonal inclusions on electronic band structure.

Crystal defects, traditionally viewed as detrimental, are now being explored for quantum technology applications. This study focuses on stacking faults in silicon and germanium, forming hexagonal inclusions within the cubic crystal and creating quantum wells that modify electronic properties. By modeling defective structures with varying hexagonal layer counts, we calculated the formation energies and electronic band structures. Our results show that hexagonal inclusions in Si and Ge exhibit a direct band gap, changing with inclusion thickness, effectively functioning as quantum wells. We find that Ge inclusions have a direct band gap and form type-I quantum wells. This research highlights the potential of manipulating extended defects to engineer the optoelectronic properties of Si and Ge, offering new pathways for advanced electronic and photonic device applications.

Interaction of sodium atoms with stacking faults in silicon with different Fermi levels

Variation in the formation energy of stacking faults (SFs) with the contamination of Na atoms was examined in Si crystals with different Fermi levels. Na atoms agglomerated at SFs under an electronic interaction, reducing the SF formation energy. The energy decreased with the decrease of the Fermi level: it was reduced by more than 10 mJ/m2 in p-type Si, whereas it was barely reduced in n-type Si. Owing to the energy reduction, Na atoms agglomerating at SFs in p-type Si are stable compared with those in n-type Si, and this hypothesis was supported by ab initio calculations.

27a-N-6 シリコン中積層欠陥の金拡散による成長・肥大と収縮・消滅

27a-N-6 シリコン中積層欠陥の金拡散による成長・肥大と収縮・消滅

Interaction of dopant atoms with stacking faults in silicon

The width of a stacking fault ribbon bound by a pair of partial dislocations in silicon crystals was unchanged when boron and gallium atoms of p-type dopant were agglomerated nearby the ribbon by annealing, even though the width increased when n-type dopant atoms were agglomerated as previously reported [Y. Ohno, Y. Tokumoto, I. Yonenaga, Thin Solid Films, accepted for publication]. The origin of the width-increase in n-type crystals was proposed as the reduction of the stacking fault energy, from 58±5 down to 46±5mJ/m2, due to an electronic interaction between the ribbon and the n-type dopant atoms, and the interaction energy was estimated to be 0.15±0.05eV. On the other hand, the interaction of p-type dopant atoms with stacking faults was not detected.

Effects of extended defects on the properties of intrinsic and extrinsic point defects in silicon

We investigated the interaction of intrinsic and extrinsic point defects with stacking faults in silicon. The calculations were carried out using ab initio total energy methods. The results show that the formation energies of intrinsic defects and impurities (P, As, and Al) are lower at the stacking fault as compared to the respective defects in crystalline environment. Therefore, stacking faults should have a large concentration of defects, and they should play an important role on the mechanisms of dislocation motion.

Thermal equilibrium concentrations and diffusivities of intrinsic point defects in silicon

Recently, inherent defects in silicon crystal cause a serious problem resulting from the trend toward small scale and highly integrated circuits used in semiconductor devices. There is no doubt that intrinsic point defects in silicon are closely related to the formation mechanisms of these defects. Understanding the behavior of the point defects is thus extremely important. The equations for dopant diffusions and oxidation stacking faults in silicon, considering the intrinsic point defect concentrations as unknowns, are solved by mathematically self-consistent method and also the mechanisms of silicon self- and dopant-diffusions are determined. The thermal equilibrium concentrations and diffusivities of self-interstitials and vacancies in silicon, ∗CI, ∗CV, DI and DV are obtained as functions of the absolute temperature T. Consequently, the relations of ∗CI<(∗CI∗CV)1/2<∗CV and ∂Tln(DV)<∂Tln(DI) are derived for an arbitrary temperature.

Point defect interactions with extended defects in semiconductors

We performed a theoretical investigation of the interaction of point defects (vacancy and self-interstitials) with an intrinsic stacking fault in silicon using ab initio total-energy calculations. Defects at the fault and in the crystalline environment display a different behavior, which is evidenced by changes in formation energy and electronic structure. The formation energies for the vacancy and the [110]-split interstitial are lower at the intrinsic stacking fault than those in the crystal, indicating that in nonequilibrium conditions, intrinsic stacking faults can act, together with other extended defects, as a sink for point defects, and also that in equilibrium conditions, there can be a higher concentration of such defects at the fault than that in bulk silicon.

On the Origins of Oxidation‐Induced Stacking Faults in Silicon

A qualitative explanation for the origins of oxidation‐induced stacking faults, OSFs, is presented. This explanation is based on vacancy annihilation by dislocations during crystal growth, which influences the distribution and size of vacancy clusters within the finished boule. A mechanism for nucleation of OSFs at small clusters of vacancies is described. © 1999 The Electrochemical Society. All rights reserved.

Point Defect Interactions with Extended Defects in Silicon

AbstractWe investigated the interaction of point defects (vacancy and self-interstitials) with an intrinsic stacking fault in silicon. The calculations were carried out using ab initio total energy methods. The results show that point defects at an intrinsic stacking fault display a different behavior as compared to the same defect in the crystalline environment. This is evidenced by differences in formation energies and electronic structures. These results suggest that there is migration of point defects from the bulk to a stacking fault. This could affect the dislocation mobility in the crystal.

Shallow electron states of bounded intrinsic stacking faults in silicon

The electronic structure of bounded intrinsic stacking faults in silicon is studied. Especially the influence of the stacking fault width on the electronic states in the band gap is investigated. The extended defect studied comprises an intrinsic stacking fault with two reconstructed 90\ifmmode^\circ\else\textdegree\fi{} partials as boundaries. The atomic structure is determined by different valence force fields. These are the Keating potential, the bond-charge model, and an anharmonic version of the bond-charge model. The electronic structure is calculated by linear combinations of atomic orbitals. Ten Gaussian-type atomic orbitals of s-, p-, and d-type are used, and up to fourth-nearest-neighbor interactions are taken into account. The levels in the band gap are evaluated by the recursion method for nonorthogonal basis functions, and by a continued fraction representation of the local density of states.

Study of Growth and Shrinkage Mechanism of Extrinsic Stacking Faults in Silicon by Gold Diffusion

Study of Growth and Shrinkage Mechanism of Extrinsic Stacking Faults in Silicon by Gold Diffusion

Dopant Diffusion and Stacking Fault in Silicon during Thermal Oxidation

Dopant Diffusion and Stacking Fault in Silicon during Thermal Oxidation

Minority and majority carrier traps associated with oxidation induced stacking faults in silicon

Majority and minority traps associated with oxidation induced stacking faults (OISFs) have been investigated by deep level transient spectroscopy and minority carrier transient spectroscopy. Electron and hole traps have been characterised in n and p type Si, and the activation energies of all extended defect related traps are found to be dependent on the occupancy of the state associated with the extended defect. Majority and minority carrier traps in n type Si exhibit non-exponential trap filling, which indicates the presence ofa significant electrostatic barrier around the OISF. The electrical properties of hole (minority) traps measured by minority carrier transient spectroscopy in n type Si are found to be different from the deep level transient spectroscopy signature of hole (majority) traps in p type Si, and this is explained by examining differences between conditions during the measurements. By examining separately the electron and hole capture properties of OISF related traps, one particular trap can be identified as a recombination centre. The capture cross-section of the OISF related hole trap in n type Si has been measured and it was found that, at low occupancy, the trap capture cross-section is 7 x 10 -14 cm 2 .

Observation of a blocking to channeling transition for MeV protons at stacking faults in silicon.

Images of stacking faults in silicon have been produced using transmitted, channeled protons. They reveal that when the proton beam angle to the ($\overline{1}\overline{1}1$) channeling planes is slightly greater than the channeling critical angle, the mean energy loss of protons passing through a stacking fault is less than that of protons passing through virgin crystal. We interpret this as being caused by the conversion of the proton trajectories from blocked to channeled owing to the lattice translation at the stacking faults. Computer simulations are shown which verify this unexpected phenomenon.

Recombination at Oxidation Induced Stacking Faults in Silicon

AbstractWe have characterised the recombination at Oxidation Induced Stacking Faults (OISF) by employing a combination of DLTS and Minority Carrier Transient Spectroscopy (MCTS). The recombination rate at traps associated with the OISF has been compared with recombination at a conventional point defect also present in the silicon. We find that the effect of small amounts of decoration by copper is to increase hole capture rates at electron filled traps. Infra Red Beam Induced Current measurements are consistent with this in that they also indicate that decoration causes enhanced recombination at the extended defects.

Electron states of a stacking fault ribbon in silicon

The electronic structure of a bounded intrinsic stacking fault in silicon is calculated. The method used is an LCAO-scheme (Linear Combinations of Atomic Orbitals) taking ten atomic orbitals of s-, p-, and d-type into account. The levels in the band gap are extracted using Lanczos' algorithm and a continued fraction representation of the local density of states. We find occupied states located up to 0.3 eV above the valence band maximum ( E v . This significantly differs from the result obtained for the ideal infinite fault for which the interface state is located at E v + 0.1 eV.

Growth and shrinkage of surface stacking faults in float-zone and Czochralski silicon

A model for the growth and shrinkage of stacking faults in silicon is presented. It accounts for interstitial traps and a nonuniform concentration of intrinsic point defects. The complete system of balance equations of intrinsic point defects is solved numerically to simulate the kinetics of stacking faults during oxidation under the assumption that float-zone silicon contains less interstitial traps than Czochralski silicon. Investigation of the influence of different interstitial trap concentrations on the growth and shrinkage of surface stacking faults shows that the kinetics of surface stacking faults is not strongly affected by the presence of interstitial traps. Surface stacking faults are expected to grow in float-zone and Czochralski silicon in a similar way.

Optical characterization of deep states associated with oxidation-induced stacking faults in silicon

Abstract We have studied the effect of sub-band gap radiation on the defects associated with the Frank partial dislocation (Burgers vector a /3(111)) bounding oxidation-induced stacking faults (OISF) in n-type silicon. We have observed the contrast produced using IR-beam-induced current (IRBIC) and have studied the effect of the modification of the contrast of individual dislocations with below band gap radiation by quenched IR-beam-induced current (QIRBIC). We have compared these spectra with absolute measurements of the photocapacitance cross-section of the dominant deep state associated with the Frank partials. QIRBIC spectra for “clean”, gold-decorated and two levels of copper-decorated samples have been measured. A model of the recombination kinetics is discussed.

Light-beam-induced transient spectroscopy of oxidation-induced stacking faults in silicon

Abstract We have applied the technique of light-beam-induced transient spectroscopy, which characterizes minority carrier capture and emission at point and extended defects, to oxidation-induced stacking faults in n-type silicon. We have compared the minority carrier trap data with conventional deep-level transient spectra for majority carrier traps. We find that we are able to distinguish between hole capture at randomly distributed point defects (e.g Au), and hole capture at point defects which are associated with the extended-defect strain field.

Comparison between the growth and shrinkage of oxidation stacking faults in silicon and silicon on insulator

We present results on the growth and shrinkage of oxidation stacking faults in silicon implanted with oxygen (SIMOX) structures and compare them with bulk silicon. The growth results show an enhanced length of the faults in SIMOX. Using the silicon direct bonding technique, we determine the critical silicon film thickness for which the length of the faults becomes the same as in bulk silicon. The shrinkage behavior of the faults during annealing in inert ambient was also studied and similar results for both materials were obtained. From these experiments we get insight into the fundamental properties of silicon self-interstitials.