Titanium silicide/germanide formation on submicron features for high mobility SiGe channel field effect transistors

The formation of self-aligned Ti(Si_(1−x)Ge_(x))₂ on submicron lines is described. The silicide/germanide is formed by reacting sputtered Ti with epitaxially grown Si_(1−x)Ge_(x) of composition and thickness relevant to high mobility Si_(1−x)Ge_(x) channel field effect transistors. Ti(Si_(1−x)Ge_(x))₂ formation on narrow lines was carried out on phosphorous doped material, because of the well known difficulties of forming silicide on heavily n-doped silicon. A companion set of boron doped blanket films was also processed. The results show that the process temperature required for the minimization of silicide/germanide sheet resistance is reduced as compared to silicide formation on Si alone. However, the silicide/germanide films agglomerate with increased high temperature processing more easily than pure silicide. The thermal stability is degraded more for films with higher Ge content and is a strong function of dopant type. Silicide/germanide formation on phosphorous doped Si_(1−x)Ge_(x) layers with x = 10% have a line width dependence similar to silicide formation. Formation on phosphorous doped Si_(1−x)Ge_(x) layers with x = 27% display an inverse line width dependence, with higher overall sheet resistance. Formation of silicide/germanide on blanket films of boron doped Si_(1−x)Ge_(x) with x = 27% behaved similar to the formation of silicide on silicon.     

Structures of the van der Waals Isomers of Halosulfuric Acids: Microwave Spectra of HX-SO3 (X = F, Cl, Br)

The effects of different doses of filgrastim on yields of CD34+ peripheral blood stem cells were evaluated in patients with breast cancer. 55 were randomized to receive filgrastim 10, 20, 30 or 40 microg/kg/d with more CD34+ cells/kg/apheresis harvested after the three highest dose levels. 35 additional patients were randomized to receive 10 or 30 microg/ kg. The median number of CD34+ cells collected after 10 microg/ kg (n = 31) was 0.7 x 10(6)/kg/apheresis (range 0.1-4.4) as compared to 1.2 (range 0.1-6.8) after 30 microg/kg (n = 32) (P = 0.04). Among patients randomized to 10 v 30 microg/kg, more (50%) achieved > or = 5.0 x 10(6) CD34+ cells/kg and less aphereses were required to achieve > or = 2.5 x 10(6) CD34+ cells/kg after the higher dose (P = 0.04). In multivariate analyses, patients receiving 10 microg/kg (n = 31) had lower yields of CD34+ cells (P = 0.026) and had a 3.3-fold increase in the probability of not achieving > or = 5.0 x 10(6) CD34+ cells/kg as compared to patients receiving 20-40 microg/kg (n = 59). Patients who had received radiation had a 2.9-fold probability of not achieving > or = 2.5 x 10(6) CD34+ cells/kg. These data suggest that, in patients with good marrow reserves, doses of filgrastim > 10 microg/kg/d mobilized more CD34+ cells and may be useful when high numbers of CD34+ cells are desired.     

Pharmacokinetics of troglitazone, a PPAR-gamma agonist, in patients with hepatic insufficiency

The natural history of multicystic dysplastic kidney (MCDK) is not well established. We analyzed kidney growth and renal function in 33 children with prenatally diagnosed unilateral MCDK in a long-term study. The mean observation period was 4.9 years with a range of 1-11.6 years. Abnormalities of the contralateral kidney were found in 10 of 33 patients (30%): ureteropelvic junction obstruction (5), ureterovesical junction obstruction (2), and vesicoureteral reflux (3). In 6 children the dysplastic kidney had been removed. Complete involution was observed in 48% and a decrease of size in 33% of 27 dysplastic kidneys. At the time of last examination, 27 of 29 children showed a volume of the contralateral kidney above the normal range (>145%). Hypertrophy of the contralateral kidney, defined as kidney length above 2 standard deviation scores (SDS), was seen in 24% of 33 children at birth, thus showing that hypertrophy of the contralateral kidney starts in utero and continues throughout childhood. The extent of contralateral hypertrophy was independent of associated abnormalities in this study. Mean creatinine was increased in the whole group (mean +1.13 SDS). Calculated creatinine clearance in 21 patients over 2 years was within normal limits, with a median of 102 ml/min per 1.73 m2 (range 84-143). Based on the results of this and previous studies, nephrectomy cannot be recommended in typical cases, but a regular follow-up of these patients seems necessary.     

Osteoporosis and bone densitometry

Osteoporosis, a clinically detectable decrease in bone density, affects 24 million Americans, placing them at increased risk for fractures. This article describes the anatomy and physiology of bones and the detection, treatment and prevention of osteoporosis. Techniques for bone densitometry are emphasized, including conventional radiography, single photon and single energy x-ray absorptiometry, dual photon absorptiometry, dual energy x-ray absorptiometry, quantitative CT and ultrasound.     

Low-temperature transport properties of RERh4B4 compounds (RE=Sm,Ho, Er,Lu)

We have measured the low-temperature electrical resistivity ρ and thermal conductivity λ of a selection of RERh₄B₄ compounds. The compound LuRh₄B₄ served as the standard material concerning superconductivity and HoRh₄B₄ as that for magnetic ordering. For ErRh₄B₄ we studied, in particular, the transition from the superconducting to the normal state with decreasing temperature. In SmRh₄B₄ both ρ(T) and λ(T) reveal the strong interaction between the magnetic moments of the Sm³⁺ ions and the conduction electrons, which is partly quenched at the transition to the antiferromagnetic state. Depending on the material considered, the thermal conductivity data are analyzed using theoretical calculations due to Bardeen, Rickayzen, and Tewordt; Kadanoff and Martin; and Ambegaokar and Griffin.     

Superconducting and magnetic properties of ErRh4B4

The thermal expansion, magnetization, magnetostriction, and ac electrical resistance of the compound ErRh₄B₄ have been measured at low temperatures. The influence of magnetic fields on the superconducting and magnetic properties of this compound is emphasized, and the qualitative behavior of the upper critical field as a function of temperature has been determined from the experiments.Research supported by the Schweizerische Nationalfonds zur Förderung der wissen-schaftlichen Forschung.Research sponsored by the U.S. Energy Research and Development Administration under Contract No. ERDA E(04-3)-34PA227.Research in La Jolla sponsored by the Air Force Office of Scientific Research, Air Force Systems Command, U.S. Air Force, under AFOSR Contract No. F49620-77-C-0009.