Thermal desorption spectroscopy evaluation of hydrogen-induced damage and deformation-induced defects

ABSTRACT

Thermal desorption spectroscopy (TDS) was performed on ultra-low carbon (ULC) steel with various degrees of hydrogen-induced damage and deformation-induced defects. First, the extent to which hydrogen-induced damage manifests itself in TDS measurements was evaluated. Application of multiple test conditions on cold deformed ULC steel with and without the presence of hydrogen-induced damage showed that such damage did not appear as a hydrogen signal on the TDS spectra. Second, interesting features observed on the TDS spectra of cold deformed ULC steel were further investigated by assessing the TDS spectra of recrystallised and annealed ULC steel. As such, the four peaks in the TDS spectra were linked to microstructural features: interstitial lattice positions, grain boundaries, dislocations and microvoids.     

Strained Si/SiGe MOS technology: Improving gate dielectric integrity

Strained Si is recognised as a necessary technology booster for the nanoelectronics regime. This work shows that high levels of stress attainable from globally strained Si/SiGe platforms can benefit gate leakage and reliability in addition to MOSFET channel mobility. Device self-heating due to the low thermal conductivity of SiGe is shown to be the dominating factor behind compromised performance gains in short channel strained Si/SiGe MOSFETs. Novel thin virtual substrates aimed at reducing self-heating effects are investigated. In addition to reducing self-heating effects, the thin virtual substrates provide further improvements to gate oxide integrity, reliability and lifetime compared with conventional thick virtual substrates. This is attributed to the lower surface roughness of the thin virtual substrates which arises due to the reduced interactions of strain-relieving misfit dislocations during thin virtual substrate growth. Good agreement between experimental data and physical models is demonstrated, enabling gate leakage mechanisms to be identified. The advantages and challenges of using globally strained Si/SiGe to advance MOS technology are discussed.     

Vitamin B1-Gehalt verschiedener Lebensmittel The thiamin-content of some foodstuffs

Zusammenfassung Es wird über den Vitamin B₁-Gehalt von verschiedenen Lebensmitteln berichtet. Es wird festgestellt, daß die papierchromatographisch ermittelten Werte häufig höher liegen als die entsprechenden Angaben in den gängigen Vitamin- bzw. Nährwerttabellen. Die Gründe werden erörtert.Es wird wahrscheinlich gemacht, daß der Mensch im Durchschnitt mehr Vitamin B₁ zu sich nimmt, als aus den Mittelwerten der in Deutschland bekannten Tabellen errechnet wird.

---

Summary The thiamin-content of some foodstuffs is investigated. The contents, being determined by a method using paperchromatography, are often higher than those of the commonly used vitamin- or food-tables. The reasons are discussed.Probably, the average intake of thiamin is infact higher than the intake calculated from food-tables commonly used in Germany.

---

---

Die Analysen wurden durchgeführt im Mag-Planck-Institut für Ernährungsphysiologie Dortmund. Damaliger Direktor: Prof. Dr. Dr. med. h. c. H. Kraut.     

Inactivation kinetics of alkaline phosphatase and lactoperoxidase, and denaturation kinetics of beta-lactoglobulin in raw milk under isothermal and dynamic temperature conditions

A detailed kinetic study of alkaline phosphatase, lactoperoxidase and beta-lactoglobulin was carried out in the context of identifying intrinsic time-temperature indicators for controlling the heat processing of milk. The heat inactivation or denaturation of alkaline phosphatase, lactoperoxidase and beta-lactoglobulin under isothermal conditions was found to follow first order kinetics. Experimental results were analysed using both a two step linear regression and a one step non-linear regression method. Results obtained using the two statistical techniques were comparable, but the 95% confidence interval for the predicted values was smaller when the one step non-linear regression method was used, indicating its superiority for estimating kinetic parameters. Thermal inactivation of alkaline phosphatase and lactoperoxidase was characterized by z values of 5.3 deg C (D60 degrees C = 24.6 min) and 4.3 deg C (D71 degrees C = 38.6 min) respectively. For the denaturation of beta-lactoglobulin we found z values of 7.9 deg C (D7.5 degrees C = 49.9 min) in the temperature range 70-80 degrees C and 24.2 deg C (D85 degrees C = 3.53 min) in the range 83-95 degrees C. Dref and z were evaluated under dynamic temperature conditions. To estimate the statistical accuracy of the parameters, 90% joint confidence regions were constructed.     

Processing factors influencing the leakage current in shallow junction diodes for deep submicro-meter CMOS

The impact of the well doping profile on the current–voltage (I-V) and capacitance–voltage (C-V) characteristics of cobalt-silicided n⁺-pp⁺-n junction diodes fabricated in a 0.18 m CMOS compatible processing scheme is studied. It will be shown that the nature of the junction (abrupt or linearly graded) has a strong influence on the resulting leakage current. Moreover, the extra thermal budget to create a nitrided gate oxide may drastically change the B-profile in the p-well and deteriorate the overall characteristics. From a detailed analysis, it is concluded that the increased leakage current observed for the nitrided case occurs at the perimeter of the diodes, where the Co-silicide may form a Schottky contact with the underlying n- or p-well. In order to control the leakage, the overall thermal budget should be optimized, particularly with respect to the back-end processing.     

Measurement of thermally induced vibrations of microelectronic devices by use of a heterodyne electronic speckle pattern interferometry imaging technique

An imaging technique to measure modulated surface displacements on microelectronic devices is presented. A device is supplied by a sinusoidal current that creates a modulated variation of temperature. To measure the induced normal surface displacement, we use an electronic speckle pattern interferometry setup in which we introduce a secondary modulation using an electro-optic modulator. To extract the displacement information, we then analyze the term atthe blinking frequency, which is equal tothe difference between the frequency of the surface displacement and the frequency of the secondary modulation. As the photodetector is a visible CC D camera, weapply heterodyne detection byusing a multichannel lock-in scheme. We have experimented with this new technique on a membrane to measure the amplitude of modulated surface displacement induced by the Joule effect.     

Hot-carrier stress effects on the amplitude of Random Telegraph Signals in small area Si p-MOSFETS

This paper studies the effect of avalanche hot-carrier (HC) stress on the amplitude of pre-existing Random Telegraph Signals (RTSs) in small area Si p-MOSFETs. It is shown that the RTS amplitude of a particular oxide trap increases after HC stress, both in linear operation and in saturation. From this, it is concluded that the effect of such a trap on the carrier transport in a small area MOSFET is also determined by the charges present at the interface and in the oxide. The impact of the observations on the RTS based modeling of flicker noise in MOSFETs will be briefly addressed.     

Present status of laparoscopic splenectomy for hematologic diseases: certitudes and unresolved issues

Laparoscopic splenectomy is considered to be the "gold-standard" treatment of benign hematologic diseases, with normal or slightly enlarged spleens. Laparoscopic treatment of malignant diseases and splenomegalies remains more controversial. The procedure requires a great surgeon's laparoscopic expertise, appropriate positioning of the patient and trocar insertion, and gentle and meticulous dissection of the spleen. The technique is feasible in 91% of the patients with a 0.9% operative mortality and a postoperative complications rate of 12%. When compared with open splenectomy in retrospective case-controlled studies, the laparoscopic approach includes a longer operative time and higher operative room costs. However, advantages include reduced postoperative hospital stay and faster return to normal activities. Despite scarce reported data, long-term hematologic cure rate seems to be equivalent in patients with idiopathic thrombocytopenic purpura. The accuracy of laparoscopic exploration to detect all accessory spleens is however questioned, and residual postoperative accessory splenic tissues have been observed. Prospective randomized controlled trials comparing short- and long-term results of open and laparoscopic splenectomies are required to confirm definitely the role of laparoscopy in the management of hematologic disorders.