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We present a study on the redistribution of boron in (100) crystalline silicon and silicon-on-insulator (SOI) substrates after rapid thermal processing (RTP). The use of SOI back-side secondary ion mass spectrometry (SIMS) technique in obtaining an accurate diffusion profile is also investigated. Our results show that the boron diffusion profiles (using conventional frontside SIMS) do not deviate in any of the two types of substrates after RTP with a soak time of 30 sec, indicating that the insulating effect of SOI substrate does not enhance the diffusion of boron. Since the profile obtained by the back-side SIMS technique is always shallower than that of front-side SIMS, it is deduced that the back-side SIMS technique gives a better representation of the real profile. [ABSTRACT FROM AUTHOR]

In this paper, we report the systematic investigation on the melt characteristics of silicon during laser thermal processing (LTP) of amorphous silicon (a-Si) gates on ultrathin gate oxides. LTP is used to reduce the gate depletion effect in advanced semiconductor devices. The influence of implantation-induced damage and chemical inhomogeneities on the melt behavior of ion-implanted a-Si is studied using in situ time-resolved reflectance (TRR) measurements and ex situ secondary ion mass spectrometry. The results from TRR measurements indicate the presence of a buried melt for a-Si implanted with B+ at a subamorphizing dose. In contrast, such a melt behavior is not observed during LTP of undoped a-Si and a-Si implanted with As+ at an amorphizing dose. We attribute the marked difference in the melt characteristics to the competitive effects between compositional inhomogeneities and the extent of amorphization in the a-Si layer. It should be noted that the as-deposited a-Si gate is not really “amorphous” in the sense of an ion beam-induced amorphous layer. This postulation is verified by the absence of a buried melt in a-Si films implanted with Si+ prior to B+ implantation, where the dose of the Si+ implant is sufficient to cause amorphization in silicon and the amorphization depth greatly exceeds the projected range of the boron implant. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The effect of preamorphization using silicon (Si) ion, different annealing temperatures and heating rates on nucleation density and grain size of C49 and C54–TiSi[sub 2] have been studied. The average grain size of C54–TiSi[sub 2] is found to decrease when the peak annealing temperature is changed from 700 to 850 °C. We found that the nucleation threshold temperature is about 900 °C at which the C54–TiSi[sub 2] grain size levels off at about 23 nm. We also found that the grain size of C54–TiSi[sub 2] is independent of different heating rates. Our results also show that preamorphization is not so effective in reducing the C54–TiSi[sub 2] grains when annealing temperature is raised to above 850 °C. However, preamorphization does improve the grain size uniformity. By optimizing the processing parameters such as peak annealing temperature, heating rates and preamorphization, we have demonstrated the formation of C54–TiSi[sub 2] on 0.12 μm polycrystalline silicon (polysilicon) lines with no agglomeration. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this article we report the role of excess interstitials in the end-of-range region in transient enhanced diffusion of boron during annealing of laser-processed samples. The results show that although the amorphous layer in preamorphized silicon can be completely annealed by laser irradiation, the end-of-range damages were not sufficiently annealed. The end-of-range region contains a supersaturation of interstitial defects that enhance the diffusion of boron during a post-laser processing anneal. It is found that the transient enhanced diffusion is significantly suppressed when the melt depth is extended beyond the amorphous layer such that the interstitial dose in the region adjacent to the laser-melted layer is minimized. In this way, the abruptness of laser-processed ultrashallow junctions can be maintained upon further annealing at moderately high temperatures. Cross-sectional transmission electron microscopy shows that a virtually defect-free regrown layer is obtained by overmelting beyond the amorphous layer into the substrate. [ABSTRACT FROM AUTHOR]

The transcriptional co-activators YAP and TAZ are downstream targets inhibited by the Hippo tumor suppressor pathway. YAP and TAZ both possess WW domains, which are important protein-protein interaction modules that mediate interaction with proline-rich motifs, most commonly PPXY. The WW domains of YAP have complex regulatory roles as exemplified by recent reports showing that they can positively or negatively influence YAP activity in a cell and context-specific manner. In this study, we show that the WW domain of TAZ is important for it to transform both MCF10A and NIH3T3 cells and to activate transcription of ITGB2 but not CTGF, as introducing point mutations into the WW domain of TAZ (WWm) abolished its transforming and transcription-promoting ability. Using a proteomic approach, we discovered potential regulatory proteins that interact with TAZ WW domain and identified Wbp2. The interaction of Wbp2 with TAZ is dependent on the WW domain of TAZ and the PPXY-containing C-terminal region of Wbp2. Knockdown of endogenous Wbp2 suppresses, whereas overexpression of Wbp2 enhances, TAZ-driven transformation. Forced interaction of WWm with Wbp2 by direct C-terminal fusion of full-length Wbp2 or its TAZ-interacting C-terminal domain restored the transforming and transcription-promoting ability of TAZ. These results suggest that the WW domain-mediated interaction with Wbp2 promotes the transforming ability of TAZ. [ABSTRACT FROM AUTHOR]

We have investigated the effect of laser annealing on the recrystallization of the preamorphized layer during the formation of ultrashallow p[sup +]/n junctions. The results from channeling Rutherford backscattering spectrometry clearly indicate that the preamorphized layer has been completely annealed with a single-pulse laser irradiation at 0.5 J/cm[sup 2]. These data are further verified by high-resolution cross-sectional transmission electron microscopy. It is proposed that the preamorphized layer has recrystallized to a single-crystalline structure via liquid-phase epitaxy. No observable extended defects are present in the recrystallized region after laser annealing. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Ultrashallow p[sup +]/n junctions formed by B[sup +]-ion implantation and annealed by spike rapid thermal annealing (RTA) or laser annealing were studied. The effect of the preamorphizing depth on the redistribution of boron atoms after annealing has also been investigated. Our results show that for ultrashallow junctions formed by ultra-low-energy ion implantation and spike RTA, the depth of the preamorphizing implant has very little impact on the junction depth. By optimizing the laser fluence and preamorphization depth, a highly activated, ultrashallow, and abrupt junction can be obtained using a 248 nm excimer laser. The secondary-ion-mass spectrometry results clearly indicate that a step-like profile with a junction depth of 370 Å (for a B[sup +] implant at 1 keV) can be formed with a single-pulse laser irradiation at 0.5 J/cm2. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]