Local Heating Technique Research Articles

In situ Raman studies of single-walled carbon nanotubes grown by local catalyst heating

Using in situ Raman spectroscopy we investigate single wall carbon nanotube growth on Mo electrodes, using a highly localized resistive heating technique. Small diameter semiconducting single wall nanotubes grow very rapidly when the catalyst support is heated to a temperature of 800 °C. The G/D ratio shows an interesting time-dependent behaviour. It first decreases, indicating the presence of amorphous carbon and then significantly increases again after ca. 5 min growth while retaining the position and shape expected for predominantly semiconducting carbon nanotubes.

Development of Novel MEMS Soldering Technique Using Self-Propagating Exothermic Reaction in Al/Ni Multilayer Films

This paper describes a novel local heat process technique for MEMS soldering technology. Al/Ni multilayer film deposited by DC magnetron sputtering shows self-propagating exothermic reaction. By applying a spark to the reactive film, the film generates heat enough to melt Au-Sn solder film. The heat of reaction depended on Al/Ni bilayer thickness and the total film thickness. We used the Al/Ni multilayer film as a local heat source in MEMS soldering packages. Au-Sn solder film-bonded silicon elements by the local heating was fabricated without other external heat sources, and the bond strength was characterized. The local heating technique by Al/Ni multilayer film's exothermic reaction would likely have the potential for MEMS soldering technology.

G231 フォトクロミックダイを利用した選択レーザー加熱手法の検討(OS-13 材料加工における熱工学関連技術III)

This paper deals with a local laser heating technique using photochromic-dye. He-Cd laser was used as excitation light source to actively control the radiation absorption coefficient of the dye added polymer material, and Ar^+ laser was used as heating light source. Both experimental and numerical simulation studies were carried out to elucidate the characteristics of the present technique. The results showed that the radiation absorption coefficient distribution in the sample thickness direction and the color attenuation effect of the dye during the heating had large effect on the temperature increase. According to the obtained knowledge, laser transmitting welding process for transparent polymer material was successfully realized.

Measurement of Index Modulation along Fiber Bragg Gratings by Side Scattering and Local Heating Techniques

A method for measurement of index modulation profile along fiber Bragg gratings is described which uses a hot finger that selectively heats some fringes. Results obtained from this local heating technique and side scattering technique are reviewed and compared.

Hyperthermia in Cancer Treatment

Hyperthermia, used as an adjunct to radiation therapy, can increase tumor regression significantly. When used as a local (as opposed to regional or systemic) modality, proper treatment requires detailed knowledge of tumor and normal tissue geometry, and physiologic parameters such as perfusion and thermal conductivity. A brief review of local heating techniques and details of two techniques used to treat brain tumors are provided: Scan Focused Ultrasound and Interstitial Ferromagnetic Seed Implants. These techniques require the most sophisticated use of diagnostic radiology methods. Data from several modalities such as CT, MRI, angiography, and xenon CT perfusion studies must be merged into a consistent data set. This data set must be indexed precisely relative to the treatment apparatus. Real-time noninvasive temperature monitoring of the treatment field has not been achieved at this time, but is of interest to researchers in hyperthermia.

Flip-chip replacement within the constraints imposed by multilayer ceramic (MLC) modules

Economics often dictates that suitable module rework procedures be established to replace solder bump devices (flip chips) reflowed to multichip carriers. These operations are complicated, owing to various constraints such as the substrate's physical and mechanical properties, close proximity of surface features, etc. This paper describes the constraints and the methods to circumvent them. An order of preference based upon the degree of constraint is recommended to achieve device removal and subsequent site dress of the residual solder left on the substrate. It has been determined that rework (device replacement) can be successfully achieved in even highly constricted situations. This is illustrated by the example of utilizing a localized heating technique, hot gas, to remove solder from microsockets from which chips were previously removed. Microsockets are areas to which chips are reflowed to the top surface of IBM's densely populated multilayer ceramic (MLC) modules, thus forming the so-called controlled collapse chip connection or C-4. The microsocket patterns are thus identical to the chip footprint.