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We present detailed B penetration studies from B-doped polysilicon through alternate gate dielectric candidate HfSixOy films. No detectible B penetration is observed for annealing times as long as 20 s after 950 °C. Considerable B incorporation into the Si substrate is observed for annealing temperatures higher than 950 °C. By modeling the B depth profiles, we calculated the B diffusivities through HfSixOy to be higher than the corresponding diffusivities for SiO2. B diffusion through grain boundaries after HfSixOy crystallization is proposed to be responsible for the enhanced B diffusivity observed.

The diffusion-bonding behavior of single-phase austenitic stainless steel depends strongly on the chemistry of the surfaces to be bonded. We found that very smooth (0.5 nm root-mean-square (RMS) roughness), mechanically polished and lapped substrates would bond completely in ultrahigh vacuum (UHV) in 1 hour at 1000 ЊC under 3.5 MPa uniaxial pressure, if the native oxide on the substrates was removed by ion-beam cleaning, as shown by in-situ Auger analysis. No voids were observed in these bonded interfaces by transmission electron microscopy (TEM), and the strength was equal to that of the unbonded bare material. No bond formed between the substrates if in-situ ion cleaning was not used. The rougher cleaned substrates partially bonded, indicating that roughness, as well as native oxides, reduced the bonding kinetics.

Phosphorus and arsenic penetration studies from P- and As-doped polycrystalline silicon through HfSixOy and HfSixOyNz (18% N) alternate gate dielectric candidates films into Si(100) are presented using a combination of chemical etching and secondary ion mass spectrometry (SIMS). Penetration is observed through HfSixOy after 1050 and 1000 °C rapid thermal annealing for As and P, respectively. In contrast, As or P dopant penetration is at the SIMS limit of detection for HfSixOyNz films. By modeling the P and As depth profiles in the Si substrate, their respective diffusivities in HfSixOy are higher than the corresponding diffusivities in SiO2. The enhanced dopant diffusivity observed in HfSixOy is proposed to be due to grain boundary formation in the dielectric after crystallization from annealing.

We discuss buffer-layer concepts for the synthesis of low defect-density HgCdTe epilayers on Si for both hybrid and monolithically integrated, infrared focalplane arrays (IRFPAa). The primary technical problems to overcome include the 19% lattice-parameter mismatch between HgCdTe and Si, and the (211)B surface orientation required for molecular-beam epitaxy (MBE), the growth technique of choice for HgCdTe. We provide a general overview of IRFPAs, motivations for realizing HgCdTe on Si, the current state-of-the-art parameters as a baseline, and three novel buffer-layer concepts and technologies based on (1) obedient GeSi films on SiO 2 , (2) wafer bonding, and (3) chalcogenides.