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The exponential growth of the silicon industry can be attributed to that fact that silicon has a native oxide that is silicon dioxide. With SiO 2 soon approaching its fundamental limit, we must find an alternate to SiO 2 or a new switch to replace MOSFETs. In this paper we focus on the leading alternate gate dielectrics. We first discuss the selection criteria for alternate gate dielectrics and why it is important to have an amorphous gate dielectric. SiO 2 and aluminum oxide remain amorphous at very high temperatures. For dielectrics with K >15 and gate power 2 , it may be necessary to stabilize the amorphous phase of metal oxides by adding Al or Si to the oxide, thus forming multi-component dielectrics such as aluminates. We then benchmark aluminates with aluminum oxide and silicon dioxide.

As new, advanced high-k dielectrics are being developed to replace SiO2 in future generations of microelectronics devices, understanding their etch characteristics becomes vital for integration into the manufacturing process. We report on the etch rates and possible mechanisms for one such dielectric, Zr1−xAlxOy (x≈0.2), in plasmas containing a mixture of Cl2 and BCl3, as a function of gas composition and ion impact energy. Higher concentrations of BCl3 enhance the etch rate as well as selectivity of Zr1−xAlxOy etching as compared to the etching of α-Si, whereas increasing ion energy increases the etching rates but decreases selectivity. In a high density helical resonator plasma, etching rates on the order of 700 A/min and 1:1 selectivity are typical. Angle-resolved x-ray photoelectron spectroscopy was used to study the composition of the upper ∼30 A of the film, before and at the end of the etching process. We found that the etching rate of Zr1−xAlxOy does not change with time for the range of Cl2/BCl3 ...

As an effort toward a goal of monolithic optoelectronics for silicon (Si) chip-to-chip connections, we have fabricated organic light emitting diodes (LED's) using either heavily N-doped silicon (Si) as a cathode or P-doped Si as an anode. A thin silicon dioxide (SiO/sub 2/) layer, thermally grown on Si before deposition of a polymer or a molecular organic layer, enhances the electron injection into the semiconducting emissive layer. Without the thin oxide layer, no light was observed from LED's made from either (2-methoxy, 5-(2'-ethyl-hexoxy)-1, 4-phenylene vinylene) (MEH-PPV) or 8-hydroxyquinoline aluminum (Alq). With the SiO/sub 2/ layer,the internal quantum efficiencies as high as 0.02% and 0.5% have been observed for MEH-PPV and Alq, respectively, and the turn-on voltages were as low as 2.5 V and 8 V, again for MEH-PPV and Alq, respectively. From the LED response time measurement, we identified RC constant and the recombination time of transport-related traps as the speed limiting factors. >

We have developed a half-micron super self-aligned BiCMOS technology for high speed application. A new SIlicon Fillet self-aligned conTact (SIFT) process is integrated in this BiCMOS technology enabling high speed performances for both CMOS and ECL bipolar circuits. In this paper, we describe the process design, device characteristics and circuit performance of this BiCMOS technology. The minimum CMOS gate delay is 38 ps on 0.5 /spl mu/m gate and 50 ps on 0.6 /spl mu/m gate ring oscillators at 5 V. Bipolar ECL gate delay is 24 ps on 0.6 /spl mu/m emitter ring oscillators with collector current density of 40 kA/cm/sup 2/. A single phase decision circuit operating error free over 8 Gb/s and a static frequency divider operating at 13.5 GHz is demonstrated in our BiCMOS technology. >

This chapter reviews emerging techniques for deep, non-invasive Raman spectroscopy of diffusely scattering media. As generic analytical tools, these methods pave the way for a host of new applications including non-invasive disease diagnosis, chemical identification and characterisation of pharmaceutical products.

An optimal device structure for integrating bipolar and CMOS is described. Process design and device performance are discussed. Both the vertical n-p-n and MOS devices have non-overlapping super self-aligned (NOVA) structures. The base-collector and source/drain junction capacitances are significantly reduced. This structure allows complete silicidation of active polysilicon electrodes, cutting down the parasitic resistances of source, drain, and extrinsic base. The critical gate and emitter regions are protected from direct reactive ion etching exposure and damage. All shallow junctions are contacted by polysilicon electrodes which suppress silicide-induced leakage. An arsenic buried layer minimizes collector resistance and collector-substrate capacitance. A novel selective epitaxy capping technique suppresses lateral autodoping from the arsenic buried layer. Fully recessed oxide with polysilicon buffer layer is used to achieve a low defect density device isolation. CMOS with L/sub eff/=1.1 mu m and W/sub n//W/sub p/=10 mu m/10 mu m exhibits averaged ring oscillator delay of 128 ps/stage. An n-p-n transistor with f/sub T/, of 14 GHz and low-power emitter-coupled logic ring oscillator with a delay of 97 ps/stage have been fabricated. >

We have fabricated and demonstrated a new device called the Vertical Replacement-Gate (VRG) MOSFET. This is the first MOSFET ever built that combines (1) a gate length controlled precisely through a deposited film thickness, independently of lithography and etch, and (2) a high-quality gate oxide grown on a single-crystal Si channel. In addition to this unique combination, the VRG-MOSFET includes a self-aligned S/D formed by solid source diffusion (SSD) and small parasitic overlap, junction, and S/D capacitances. The drive current per /spl mu/m of coded width is significantly higher than that of advanced planar MOSFETs because each rectangular device pillar (with a thickness of minimum lithographic dimension) contains two MOSFETs driving in parallel. All of this is achieved using current manufacturing methods, materials, and tools, and competitive devices with 50-nm gate lengths (L/sub G/) have been demonstrated without advanced lithography.

BiCMOS technology which merges optimal CMOS and bipolar device structure is reported. Based on a nonoverlapping super-self-aligned structure (NOVA), the latest 1.5- mu m CMOS and ECL (emitter-coupled logic) ring oscillators have minimum delays of 110 ps/stage and 87 ps/stage, respectively. A frequency divider operating up to 4.6 GHz has been fabricated. A multiplexer and demultiplexer function up to 5.1 Gb/s. In addition to double self-alignments, a unique epi/isolation scheme combining lateral autodoping free epi deposition with a new fully recessed oxide process have been developed. This approach significantly simplifies the isolation process and is an important factor in achieving high speed with a conservative 1.5- mu m design rule. >

It is demonstrated that high-speed bipolar and CMOS processes can be merged without compromise on either device. A NOVA (nonoverlapping super self-aligned) structure with an advanced epi/isolation process that reduces parasitic capacitances and resistances is reported. The scheme combines lateral autodoping free epi deposition with a novel fully recessed oxide process. This approach significantly simplifies the isolation process and is an important factor in achieving high speed with a conservative 1.5- mu m design rule. A high-speed frequency divider, a multiplexer, and a demultiplexer operating up to 4.1 GHz, 5.5 Gb/s, and 6.2 Gb/s, respectively, have been fabricated. The results show that NOVA BiCMOS is suitable for Gb/s digital VLSI application. >

The design and implementation of 0.15- mu m-channel N-MOSFETs with very high current drive and good short channel behavior at room temperature are discussed. Measured subthreshold characteristics show a slope of 84 mV/dec and a shift for 75 mV for Delta V/sub ds/=1 V. A peak g/sub m/ of 570 mS/mm was recorded, leading to a unity-current-gain cutoff frequency (f/sub T/) of 89 GHz. Key process steps include the formation of 40-AA gate oxides and sub-500-AA junctions. Vertical doping engineering was used to minimize doping at the surface and beneath the junctions, while maintaining good turn-off characteristics. >

An ultra-high-speed half-micron non-overlapped super self-aligned BiCMOS technology that uses a silicon fillet self-aligned contact technology (SIFT) for both bipolar and MOS transistors is discussed. The SIFT process reduces the device capacitances and series resistances by minimizing the diffusion region area as well as the polysilicon electrode area. Deep trench isolation for bipolar transistors allows the device area to be much reduced for VLSI applications. The ECL gate delay is demonstrated to be 31 ps for devices with emitter polysilicon widths of 0.6 mu m. The CMOS ring oscillator gate delays are 58 ps for 0.5- mu m gate length and 67 ps for 0.6- mu m gate length at 5 V. >

The authors present the process optimization and device characteristics of a half-micron super self-aligned BiCMOS technology. With a new emitter/base process in their BiCMOS flow, bipolar transistor power gain cutoff frequency, f/sub max/, has been increased from 25.9 GHz to 33.5 GHz. Since all the process parameters related to CMOS are kept constant, high speed CMOS circuit operation is maintained without compromise. The measured nominal CMOS gate delay with a gate length of 0.5 mu m is 47 psec at 5V and 54 psec at 3.3V. >

We report a room temperature, 0.1 /spl mu/m CMOS technology on bulk Si substrates that delivers a record ring-oscillator gate delay of 11.8 psec at 2.5 V. Frequency dividers at 2.0 V operate with input frequencies exceeding 8.5 GHz. Feature sizes obey g-line lithography design rules except at the gate level. The high speed CMOS performance and the good subthreshold and drain characteristics for both NMOS and PMOS devices are obtained through the implementation of vertical doping engineering and the reduction of parasitics. >

A 1296-port MEMS transparent optical crossconnect with 5.1dB/spl plusmn/1.1dB insertion loss at 1550 nm is reported. Measured worst-case optical crosstalk in a fabric was n38 dB and nominal switching rise/fall times were 5 ms. A 2.07 petabit/s switch capacity was verified upon cross-connecting a forty-channel by 40 Gb/s DWDM data stream through a prototype fabric.

The exponential growth of the silicon industry can be attributed to that fact that silicon has a native oxide that is silicon dioxide. With SiO/sub 2/ soon approaching fundamental limit, we must find an alternate to SiO/sub 2/ or a new switch to replace MOSFET. In this paper we focus on leading alternate gate dielectrics. We first discuss the selection criteria for alternate gate dielectrics and why it is important to have an amorphous gate dielectric. SiO/sub 2/ and aluminum oxide remain amorphous at very high temperatures. For dielectrics with K > 15 and gate power < 100mW/cm/sup 2/, it may be necessary to stabilize the amorphous phase of metal oxides by adding Al or Si into the oxide; and thus forming multi-component dielectrics such as aluminates or silicates. At present, the most critical issue facing the high K research is the reduced mobility and therefore the effective fixed charge at the dielectric/Si interface. In this paper, we also shed some light on the effective fixed charge in group-three metal oxides.

We have investigated a new class of high K gate dielectric materials, Si-doped aluminates. These dielectrics, with TiN gates, can withstand high temperature CMOS processing and therefore do not require replacement gate technology. In this paper we focus on Si-doped zirconium aluminate (Zr-Al-Si-O), with K/spl sim/20. With the TiN gate stack subjected to the standard CMOS thermal budget, we have scaled this dielectric to t/sub eq//spl sim/1.2 nm with leakage current 15) may be viable alternate gate dielectrics.

We present the first p-channel Vertical Replacement-Gate (VRG) MOSFETs. Like the VRG-nMOSFETs demonstrated last year, these devices show promise as a successor to planar MOSFETs for highly-scaled ULSI. Our pMOSFETs retain the key features of the nMOSFETs and add channel doping by ion implantation and raised source/drain extensions (SDEs). We have significantly improved the core VRG process to provide high-performance devices with gate lengths of 100 nm and below. Since both sides of the device pillar drive in parallel, the drive current per /spl mu/m of coded width can far exceed that of planar MOSFETs. Our 100 nm VRG-pMOSFETs with t/sub ox/=25 /spl Aring/ drive 615 /spl mu/A//spl mu/m at 1.5 V with I/sub OFF/=8 nA//spl mu/m-80% more drive than specified in the 1999 ITRS Roadmap at the same I/sub OFF/. We demonstrate 50 nm VRG-pMOSFETs with t/sub ox/=25 /spl Aring/ that approach the 1.0 V roadmap target of I/sub ON/=350 /spl mu/A//spl mu/m at I/sub OFF/=20 nA//spl mu/m without the need for a hyperthin (

A one-mask metal-insulator-metal (MIM) capacitor using damascene Ca as the bottom electrode has been developed. Using a PECVD SiN as both the capacitor dielectric and the diffusion barrier for Cu we have demonstrated for the first time, the achieving of low leakage, high linearity MIM capacitors directly on Cu. The leakage and breakdown characteristics of the MIM capacitor depend strongly on both the surface conditions of the damascened Cu and on the PECVD SiN. We found that multilayered SiN is superior than single layer SiN, and Cu CMP plays an important role. However, the inevitable dishing on large area capacitors during Cu CMP shows little impact on the electrical characteristics.

We have integrated HfO/sub 2/ and Al/sub 2/O/sub 3/ gate dielectrics grown by atomic layer chemical vapor deposition (ALD) with poly-Si gate electrodes in the vertical replacement-gate (VRG) MOSFET geometry. These transistors are among the first reported with ALD HfO/sub 2/ gate dielectrics, and have HfO/sub 2/ target equivalent oxide thicknesses (tEOT's) down to 13 /spl Aring/. The poly-crystalline HfO/sub 2/ films in these VRG nMOSFETs exhibit extremely low gate leakage (GL) current densities of J/sub G/ /spl sim/ 10/sup -7/ A/cm/sup 2/ at V/sub G/-V/sub T,Long/ = 0.6 V for 15 /spl Aring/ tEOT devices. This indicates that amorphous gate dielectrics may not be necessary to meet GL requirements. HfO/sub 2/ devices with 50 nm gate length L/sub G/ exhibit drive currents [normalized by the coded width W/sub C/] of 490 /spl mu/A//spl mu/m for 1 V operation (overdrive V/sub GS/-V/sub T/ = 0.6 V) with good short-channel performance. These results demonstrate that ALD is compatible with the demanding VRG geometry, thereby illustrating that it should be well-suited to essentially any novel device structure built with Si-compatible materials.

The authors report the implementation of deep-submicrometer Si MOSFETs that at room temperature have a unity-current-gain cutoff frequency (f/sub T/) of 89 GHz, for a drain-to-source bias of 1.5 V, a gate-to-source bias of 1 V, a gate oxide thickness of 40 AA, and a channel length of 0.15 mu m. The fabrication procedure is mostly conventional, except for the e-beam defined gates. The speed performance is achieved through an intrinsic transit time of only 1.8 ps across the active device region. >

An effective way to suppress lateral autodoping from the heavily arsenic-doped buried layer during silicon epitaxy is described. By using this simple technique, collector-substrate capacitance (C/sub cs/) is minimized. This process is ideal for high-speed BiCMOS and bipolar technology. A thin epilayer is first grown selectively on the buried layer. This selectively grown film suppresses the release of arsenic during the subsequent epi growth. High-performance bipolar devices have been fabricated in this epi material. Electrical measurements indicate that the crystalline quality is excellent. >

The authors have developed digital confocal Raman microscopy. In this 3-dimensional technique, a stack of Raman images is taken at intervals of 0.1--2 microns through the depth of the sample. The point spread function of the microscope is then deconvolved from the images, to yield a stack of sharply depth-resolved images. A constrained iterative deconvolution, which is computationally expensive, is used. The technique efficiently uses the available laser power and makes confocal Raman imaging possible. The procedure has been used on a number of polymeric samples, including polystyrene beads and polyester gratings, and shown to work well. The computation time has recently been reduced from about 45 minutes to about 2 minutes, using a digital signal processor (DSP) instead of the CPU of the general purpose workstation previously employed. In collaboration with a major glass maker, the authors have recently employed confocal Raman microprobe spectroscopy and imaging to identify and image potassium sulfate and molecular sulfur inclusions in glass pellets. The authors have also used the Raman spectrum of water as a non-invasive temperature probe in operating electrophoresis capillaries. The paper also describes a simple macro-scale imager that was constructed, explorations of holographic optical elements, and a micron-diameter silver probe for obtaining micron-resolved surface-enhanced Raman spectra.

Confocal Raman microscopy was developed and used to study molecular sulfur inclusions in glass pellets. The Raman spectrum of water was used as a noninvasive temperature probe in operating electrophoresis capillaries. A macro-scale imager was used to image water Raman scattering using 30 mW 532 nm; it can be used to map boundaries, impurity distributions, and morphological changes in polymers and ceramics. A holographic beam splitter was obtained. Surface-enhanced Raman spectra was obtained from inside zebra fish embryos as a model system. Future research plans are given.

We have constructed a Hadamard transform Raman microscopic imaging system, and have developed it to a high definition (64K pixel) technique. We have demonstrated multispectral Raman imaging and developed the first three-dimensional (digital confocal) Raman imaging. We have explored the systematic errors in Hadamard multiplexing techniques and developed corrections. We have used our Raman microscope techniques to explore defect distributions on graphite electrodes and damage effects on SERS-activated silver electrodes. We have used the microprobe capabilities of our instrument to investigate the kinetics of polyacrylamide formation in electrolysis capabilities. We have worked closely with a manufacture of holographic displays to develop and incorporate holographic filters and holographic beam splitters into Raman spectrographs and microscopes. Finally, we have developed Hadamard multiplexing techniques for densitometric measurements of protein or nucleic acid blots.

We have constructed a Hadamard transform Raman microscopic imaging system, and have developed it to a high definition (64K pixel) technique. We have demonstrated multispectral Raman imaging and developed the first three-dimensional (digital confocal) Raman imaging. We have explored the systematic errors in Hadamard multiplexing techniques and developed corrections. We have used our Raman microscope techniques to explore defect distributions on graphite electrodes and damage effects on SERS-activated silver electrodes. We have used the microprobe capabilities of our instrument to investigate the kinetics of polyacrylamide formation in electrolysis capabilities. We have worked closely with a manufacture of holographic displays to develop and incorporate holographic filters and holographic beam splitters into Raman spectrographs and microscopes. Finally, we have developed Hadamard multiplexing techniques for densitometric measurements of protein or nucleic acid blots.

Summary form only given. Vertical doping engineering was used to implement deep-submicrometer Si MOS devices with excellent room-temperature turn-off and turn-on characteristics, circumventing the conventional scaling obstacles. The vertically engineered doping profile was realized using a 90-keV 1*10/sup 13/ cm/sup -2/ BF/sub 2//sup +/ implant for NMOS and a 100-keV 1*10/sup 13/ cm/sup -2/ As/sup +/ implant for PMOS, and minimal subsequent thermal treatment, for devices with 0.15- mu m minimum effective channel length, 4.0-nm thermally grown gate oxides, and self-aligned silicides on source, drain, and poly-gate. Room-temperature measurements show transconductances of 570/230 mu S/ mu m, threshold voltages of 0.45/-0.3 V, and subthreshold slopes of 84/88 mV/dec for NMOS/PMOS devices with a power supply voltage of 1.5 V. >

Most estimates of the radiation dose lethal to 50 per cent of a human population are based on historical data taken from well-known experiences reflecting inadequately known physical and biological conditions, or from medical procedures where individual patients received advantages of modern clinical care. It has been debated as to whether the experience of unprotected man would more closely reflect that of hospital patients or of the radiobiological studies with large animals. The issue at question is whether the apparent two-fold or more increased susceptibility of large animals to death from bone marrow damage (compared with the majority of estimates for man) is due more to true interspecies differences or the lack of medical support. This study is an attempt to assess the radiosensitivity of unprotected man in terms of the composite animal experiments. Based upon an extensive data base containing 121 separate animals studies using 13 different species, an estimate of the mortality dose-response relationship due to a uniform, continuous field of photon radiation is predicted for 70 kg unprotected man. Man is assumed to have a level of radiation sensitivity similar to that of the species represented in the data base, after adjustment for body weight. The mathematical model used includes fixed terms to account for effects of body weight and dose rate, and random terms reflecting inter- and intra-species variation and experimental error. Point predictions and 95 per cent prediction intervals are given for the LD05, LD10, LD25, LD50, LD75, LD90, and LD95, for dose rates ranging from 0.01 to 0.5 Gy/min, and treatment times ranging from about 2 min to about 24 h. At 1 cGy/min our point prediction of the LD50 is 299 cGy with an associated 95 per cent prediction interval of (168 cGy, 535 cGy). The analogous values at 50 cGy/min are 183 cGy and (103 cGy, 326 cGy).

Many radiation-induced lethality experiments have been published for various mammalian species. From those studies a subset of studies reflecting useful biological and physical variables has been compiled into a database suitable to study interspecific variability of radiosensitivity, dose-rate dependence of sensitivity, dose-response behavior within each experiment, etc. The data compiled were restricted to continuous and nearly continuous exposures to photon radiations having source energies above 100 keV. Photon source energy, exposure geometry, and body weight considerations were used to select studies where the dose to hematopoietic tissue was approximately uniform. The database reflects 13 mammalian species ranging in size from mouse to cattle. Some 211 studies were compiled, but only 105 were documented in adequate detail to be useful in development and evaluation of dose-response models of interest to practical human exposures. Of the 105 studies, 70 were for various rodent species, and 35 were for non-rodent groups ranging from standard laboratory primates (body weight approximately 5 kg) to cattle (body weight approximately 375 kg). This paper considers seven different dose-response models which are tested for validity against those 105 studies. The dose-response models include: right-skewed extreme value, left-skewed extreme value, log-logistic, log-probit, logistic, probit, and Weibull models. In general, the log transformation models did not improve model performance and the extreme value models did not seem consistent with the preponderance of the data. Overall, the probit and the logistic models seemed preferable over the Weibull model.

Persistent hyperbetalipoproteinemia has been reported in two male Rhesus monkeys. Blood lipid studies suggest that these animals have primary Type II hyperlipoproteinemia.

1. 1. Twenty-six of 92 diabetic patients showed coronary thrombosis. Twenty cases of coronary artery thrombosis occurred in the sixth and seventh decades. 2. 2. Coronary thrombosis occurred more frequently in the diabetic than in the nondiabetic female patient. 3. 3. In both diabetic and nondiabetic patients coronary thrombosis occurred predominantly in the sixth and seventh decades. 4. 4. Of 100 diabetic patients past the age of 40 years, 34 showed coronary thrombosis and 45 coronary sclerosis. Seventy-nine had atherosclerosis of the aorta. Seventy showed arteriosclerosis and arteriolosclerosis of the kidneys. Nineteen had gangrene of the lower extremities. Hypertension was present in 44 cases. 5. 5. Coronary thrombosis occurred twice as frequently in diabetic as in nondiabetic patients. 6. 6. The opinion is expressed that both coronary thrombosis and diabetes in individuals over the age of 40 years are manifestations of degenerative vascular disease.

Ponies fasted for up to 8 days showed, both by agarose electrophoresis and preparative ultracentrifugation, the appearance of a pre-β-migrating, very low density lipoprotein fraction in plasma. This lipoprotein differs from the very low density lipoprotein found in humans and rats in that it contains a relatively smaller amount of total cholesterol, 85% of which is present in the unesterified form. By the 8th day of fasting, plasma triglyceride concentrations had increased from a prefasting level of 20 mg/dl to as high as 1000 mg/dl. The increase in plasma lipid concentrations as a result of fasting was highly variable. Accumulation of plasma cholesterol and triglyceride after injection of Triton WR 1339 was not related to the degree of fasting hyperlipidemia. This suggests that the hyperlipoproteinemia of fasting may result from an impaired utilization of very low density lipoproteins.

Investigations of the major procedural steps in a micro-BEI technique by the ceric oxidation method have been conducted. These studies have shown ( a ) essentially complete thyroxine recovery from serum is accomplished by two 8–10 vol butanol extractions, ( b ) two equal-volume Blau's reagent washes accomplish essentially complete iodide and tyrosine removal from the butanol extract, ( c ) oxidative splitting of 3,5- and 3′,5′-thyroxine iodide by ceric ion under the present conditions is rapid and complete, ( d ) chloride ion accentuates the catalytic effect of iodide in the decolorization (reduction) of ceric ion by arsenite without itself exerting a catalytic effect, and (e) coefficient of variation of the method over the range of 5 to 15 μg% BEI is about 5 to 8%. The present method, although subject to inhibition by serum and reagents, gives consistent results and offers precision equivalent to PBI techniques with the advantages of simplicity, specificity, and speed. The entire procedure requires only six to seven hours.

A simple, rapid method for the determination of cholesterol in plasma and tissue using o-phthalaldehyde is presented. Comparison of this method with the FeCl(3) method gave identical results. However, the o-phthalaldehyde determination is three times more sensitive than the FeCl(3) determination (molar extinction coefficients of 11,610 and 33,440 for FeCl(3) and o-phthalaldehyde, respectively), it takes less time to complete, and the color developed is more stable. The o-phthalaldehyde method can be used to assay free and esterified cholesterol directly after thin-layer chromatographic separation.

An ideal device structure for integrating bipolar and CMOS is reported in this paper. Both the vertical npn and MOS devices have new non-overlapping super self-aligned structures. With a single 5V supply, averaged per stage delay of 82ps and 125ps have been measured for 0.6µm and 0.85µm (L eff ) CMOS ring oscillators. Bipolar transistors have also been fabricated with a nominal current gain of 100.

The relation of plasma and adrenal gland sterols to corticosterone has been studied in the rabbit after feeding cholesterol-4- 14 C for 19–35 days. The specific activity of blood cholesterol was about 35% that of dietary cholesterol. The specific activity of the adrenal gland cholesterol was found to be about 77% that of blood cholesterol. Corticosterone specific activity was the same as adrenal gland cholesterol specific activity. Some 14 C-sterol(s) other than cholesterol were present in the adrenal gland but did not appear to be present in blood.

Summary Male New Zealand rabbits were fed control and 0.2 % cholesterol supplemented diets with and without estrogen for 90 days. Estrogen supplementation was given to one group of animals. Increased plasma and aorta lipids were observed in cholesterol fed rabbits. The added estrogen had no influence on these parameters of lipid metabolism. Adrenal gland hypertrophy was observed in all cholesterol fed animals in association with increased cholesterol content of the adrenal gland. Testicular weight were unaffected by cholesterol feeding. Thyroid function parameters which included plasma PBI, plasma thyroxine 131I resin uptake, thyroid radioiodine uptake, thyroid gland iodoaminoacid 131I fractionation, and iodide excretion by the kidney did not differ in control and cholesterol fed animals. Corticosterone secretion rates were also similar in control and cholesterol fed rabbits.

1. 1. A method for the determination of cholesterol using radioactive digitonin is reported. 2. 2. The sensitivity of this technique is comparable to other microtechniques. 3. 3. The specificity of radioglycoside analysis is comparable with ferric chloride colorimetric measurement as determined in tissues obtained from the human, monkey, rabbit, and rat. 4. 4. Specific activity measurements of dog tissue C 14 -cholesterol have been made by double isotope counting and the values obtained by H 3 -digitonin and ferric chloride compared favorably in the tissues studied, with the exception of the adrenal gland.

A 72/spl times/72 wavelength-selective crossconnect switch, that is scalable to 1296/spl times/1296 with current technology, is presented. Silica-on-silicon wavelength multiplexers with integrated monitoring taps and a MEMS micromirror array were assembled in a hybrid 3D beam steering crossconnect having 20 dB insertion loss, 100 GHz channel spacing and 30 GHz passbands.