General trends in integrated circuit technology toward smaller device dimensions, lower thermal budgets, and simplified processing steps present severe physical and engineering challenges to ion implantation. These challenges, together with the need for physically based models at exceedingly small dimensions, are leading to a new level of understanding of fundamental defect science in Si. In this article, we review the current status and future trends in ion implantation of Si at low and high energies with particular emphasis on areas where recent advances have been made and where further understanding is needed. Particularly interesting are the emerging approaches to defect and dopant distribution modeling, transient enhanced diffusion, high energy implantation and defect accumulation, and metal impurity gettering. Developments in the use of ion beams for analysis indicate much progress has been made in one-dimensional analysis, but that severe challenges for two-dimensional characterization remain. The breadth of ion beams in the semiconductor industry is illustrated by the successful use of focused beams for machining and repair, and the development of ion-based lithographic systems. This suite of ion beam processing, modeling, and analysis techniques will be explored both from the perspective of the emerging science issues and from the technological challenges.

Secondary ion mass spectroscopy (SIMS) has been used to measure the diffusion of deuterium in hydrogenated amorphous silicon. For a film deposited in a dc glow discharge in SiH4 at a substrate temperature of 315 °C, the diffusion data fits D (T) =1.17×10−2 exp(−1.53 eV/kT) cm2/s. This result implies that degradation of these films due to hydrogen out-diffusion at 100 °C will not be significant until after more than 104 years.

The spatial stability of the soluble p-dopant molybdenum tris[1-(methoxycarbonyl)-2-(trifluoromethyl)ethane-1,2-dithiolene] in polymer and polymer blend films is investigated via secondary ion mass spectrometry and current-voltage measurements. Bi-layer and tri-layer model structures, P3HT/doped P3HT and P3HT:ICBA/doped P3HT/P3HT:ICBA respectively, are fabricated using soft-contact transfer lamination to study the diffusion of the dopant. While the dopant is very mobile in pure P3HT, it is far more stable at the interface with the P3HT:ICBA bulk heterojunction. Our findings suggest a promising route to achieve spatially-confined doping with long-term stability, leading to hole-collection/injection contacts for all-solution processed polymer devices.

Eleven synthetic silicate and phosphate glasses were prepared to serve as reference materials for in situ microanalysis of clinopyroxenes, apatite and titanite, and other phosphate and titanite phases. Analytical results using different micro‐analytical techniques showed that the glass fragments were homogeneous in major and trace elements down to the micrometre scale. Trace element determinations using inductively coupled plasma‐mass spectrometry (ICP‐MS), multi‐collector inductively coupled plasma‐mass spectrometry (MC‐ICP‐MS), laser‐ablation inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) and secondary ionisation mass spectrometry (SIMS) showed good agreement for most elements (Li, Be, B, Cs, Rb, Ba, Sr, Ga, Pb, U, Th, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Er, Tm, Yb, Lu, Zr, Hf, Ta, Nb) studied and provide provisional recommended values.

Several models of boron neutralized by atomic hydrogen in silicon were tested by secondary ion mass spectrometry and infrared spectrometry. The hydrogen concentration is comparable to that of boron. Boron neutralization appears as a drop in free-carrier absorption and as an increase in resistivity. A new infrared vibrational mode attributed to 〈111〉 vibrations of H tied to Si appears at 1875 cm−1.

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Depth profiling by secondary ion mass spectrometry is described with emphasis on three important aspects: (1) depth resolution, (2) dynamic range and (3) sensitivity. It is shown how, for samples which do not roughen during sputtering, depth resolution is limited by atomic mixing effects and the flatness of the analyzed area. The dynamic range of depth profiles is shown to be limited by (a) crater edge effects, (b) neutral beam effects and (c) several types of instrumental background. These include mass spectral overlap, residual gas contamination, redeposition and ‘memory’ effects, and detection of unfilterable particles. In the absence of measurable background, sensitivity is shown to be related to analyzed area and depth resolution.

Gallium arsenide (GaAs) encapsulated at 450 °C with thin films of amorphous silicon has been annealed at temperatures up to 1050 °C and the resulting polysilicon (poly-Si)/GaAs interfaces investigated with secondary ion mass spectroscopy, Rutherford backscattering, and transmission electron microscopy. Little or no interdiffusion is detected at undoped Si/GaAs interfaces whereas Si diffuses from P- or As-doped Si to depths as great as 550 nm in the GaAs after 10 s at 1050 °C. The flux of Si into the GaAs is correlated with the flux of Ga and As into the Si and both increase with increases in the dopant concentration of the Si. The diffusion of other Si dopants into the GaAs, including P and In, is also detected. This enhanced diffusivity of Si, P, and In in GaAs results from the diffusion of point defects into the GaAs created by the diffusion of the Ga and As into the encapsulant. Numerical simulations using position-dependent impurity diffusion coefficients predict that Si, P, and In diffusivities in GaAs at doped poly-Si interfaces are enhanced by factors of 104 above their respective intrinsic bulk equilibrium diffusivities, where known.