Cross-sectional electron microscopy observation on the amorphized indentation region in [001] single-crystal silicon

AbstractWe present an experimental study on a single crystal silicon (SCS) bar subjected to pure torsion using MEMS micro instruments. The bar is in the form of a pillar, anchored at one end to the silicon substrate. It is attached to a lever arm at the other end. The pillar has a minimum cross sectional area at its mid height. The cross section coincides with the (100) plane of SCS. Torsion is generated by applying two equal forces on the lever arm on either side of the pillar. Two micro instruments apply the forces. Each consists of an electrostatic actuator and a component that calibrates it. The actuator generates high force (≈ 200 µN at 50 V) and is capable of developing large displacements (≈ 10 μm). Calibration involves determination of the force generated by the actuator at an applied voltage, as well as the linear and higher order spring constants of its springs. Each microinstrument is thus calibrated independently.With the application of forces by the two micro instruments, a torque is generated which twists the pillar. The angle of twist at different applied voltages are recorded using an angular scale. The corresponding torques are determined from the calibration parameters of the actuators. Torque is applied until the pillar fractures. Two such sample pillars, samples 1 and 2, are tested. There cross sectional areas are 1 and 2.25 µm2. We find that both the pillars behave linearly until failure. The stresses prior to fracture are evaluated based on anisotropic theory of elasticity. Samples 1 and 2 fail at shear stresses of 5.6 and 2.6 GPa respectively. The fracture surfaces seem to coincide with the (111) plane of SCS.

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A study of 2 MeV oxygen implantation to form deeply buried SiO2 layers

Journal of Materials Research ◽

10.1557/jmr.1989.1227 ◽

1989 ◽

Vol 4 (5) ◽

pp. 1227-1232 ◽

Cited By ~ 10

Author(s):

J. J. Grob ◽

A. Grob ◽

P. Thevenin ◽

P. Siffert ◽

C. d'Anterroches ◽

...

Keyword(s):

Single Crystal ◽

Single Crystal Silicon ◽

Single Step ◽

Annealing Process ◽

Dislocation Network ◽

Crystal Silicon ◽

Cross Sectional ◽

Transmission Electron ◽

Distribution Moments ◽

Best Fit

Oxygen ions were implanted into (100) oriented single crystal Si at energies in the range of 0.6 to 2 MeV at normal and oblique (60°) incidences. Oxygen concentration profiles were measured using the 16O(d, α)14N nuclear reaction for 900 keV deuterons. The experimentally measured oxygen distributions were subsequently fitted to the theoretical profiles calculated assuming the Pearson VI distribution. The distribution moments (Rp, ΔRp, ΔR⊥ skewness, and kurtosis) were deduced as the best fit parameters and compared to the computer simulation results (TRIM 87 and PRAL). Whatever the calculation method, the measured Rp and ΔRp values are close to those predicted by the theory. Deeply buried SiO2 layers were formed using a single step implantation and annealing process. A dose of 1.8 × 1018/cm2 of 2 MeV O+ was implanted into the Si substrate maintained at a temperature of 550 °C. The implanted samples were characterized using the Rutherford backscattering (RBS)/channeling technique and cross-sectional transmission electron microscopy (XTEM). The implanted samples were subsequently annealed at 1350 °C for 4 h in an Ar ambient. The annealing process results in creating a continuous SiO2 layer, 0.4 μm thick below a 1.6 μm thick top single crystal silicon overlayer. The buried SiO2 layer contains the well-known faceted Si inclusions. The density of dislocations within the top Si layer remains lower than the XTEM detection limit of 107/cm2. Between the Si overlayer and the buried SiO2 a layer of faceted longitudinal SiO2 precipitates is present. A localized dislocation network links the precipitates to the buried SiO2 layer.

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Electron Microscopy and the Electronics Industry: Partners in Development

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100178811 ◽

1990 ◽

Vol 48 (1) ◽

pp. 12-13

Author(s):

W. F. Brinkman

Keyword(s):

Electron Microscopy ◽

Solid State ◽

Single Crystal ◽

Single Crystal Silicon ◽

Microscopic Analysis ◽

Crystal Form ◽

Electronics Industry ◽

Crystal Silicon ◽

Free Material ◽

The Relationship

Since the invention of the transistor and the birth of the solid-state electronics industry, electron microscopy has been an integral part of the boom in the science and technology of semiconductors. The relationship has been symbiotic: the technique of microscopy has probably gained almost as much as the electronics industry from innovations. Historically, semiconductor research has always come down to a question of the growth of perfect materials with perfect interfaces, and microscopic analysis below the optical level has been essential to improvements. When applications for the semiconductors germanium and silicon were discovered in solid-state devices, its became necessary to grow high-quality single crystals free of defects. A lot of work at Bell Labs and other institutions was directed at understanding the behavior of dislocations in crystals. Bill Schockley, a co-inventor of the transistor, is well-known for his contributions to dislocation theory, particularly dislocation dissociation in semiconductors. Bob Heidenreich, from Bell Labs, contributed much to the early stages of microscopy of defects and dislocations. The need for dislocation-free material generated extensive efforts around the world which led to the growth of high-purity single-crystal silicon in the 1960’s. Silicon is now the highest quality and purest material available, and also the cheapest in single-crystal form.

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