The effects of preamorphizing ion mass on the end-of-range (EOR) damage and subsequent enhanced diffusivity have been investigated. Amorphizing silicon with implants of 22 keV 28Si+, 32 keV 73Ge+, 40 keV 119Sn+, and 45 keV 207Pb+ provided the mass comparisons. Cross-sectional transmission electron microscopy analysis showed that the amorphous layer depths were approximately 400 Å. After postimplantation annealing at 750 °C for 30 min, plan-view transmission electron microscopy (PTEM) revealed that increasing the ion mass decreased the defect size and density. Quantitative analysis of PTEM results also showed that increasing ion mass decreased the population of interstitials trapped in the EOR. Secondary ion mass spectrometry depth profiles of grown-in boron marker layers showed that increasing the ion mass decreased the time average diffusivity enhancements of boron (〈DB〉/DB*).

The microstructures of in situ boron-doped silicon films deposited by low-pressure chemical vapor deposition using SiH4 and BCl3 source gases on SiO2 substrates have been characterized. As-deposited films have a decreasing sheet resistance with increasing boron concentration up to 3.1±0.6×1021/cm3, and are polycrystalline. As the boron concentration exceeds 3.1±0.6×1021/cm3, the sheet resistance increases dramatically. It is shown that as the boron concentration in the silicon film exceeds 3.1±0.6×1021/cm3, the films transition from a completely polycrystalline phase to a combination of polycrystalline and amorphous phases as deposited. The amorphous phase has a higher boron concentration than the polycrystalline phase, as shown by selective Auger electron spectroscopy and secondary ion mass spectrometry. The relative fraction of amorphous phase can be controlled by boron concentration.

Damage introduced by dynamic secondary ion mass spectrometry (SIMS) depth profiling is studied. A silicon sample with a boron marker layer was depth profiled by dynamic SIMS. After subsequent annealing at 750 °C for 30 min, the SIMS sample was reanalyzed by plan-view transmission electron microscope (PTEM) and SIMS. PTEM images showed the presence of interstitial defects near the original SIMS crater, and SIMS depth profiles of similar regions exhibited boron diffusivity enhancements. Excess interstitials were introduced into the Si surface up to 2 mm from the original 225 μm×225 μm crater. Both PTEM and SIMS results showed that the damage and its effects diminished with an increase in distance from the original crater.

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Strain in B-implanted laser thermal processed ͑LTP͒ silicon is reduced by coimplantation of In. Strain in the codoped layer is calculated using lattice constants measured by high-resolution x-ray diffraction. Compensation of the strain with increasing In dose corresponds to suppression of the carrier deactivation during post-LTP annealing.