High rate deep Si etching using SF₆/O₂ gas chemistry by Magnetically-Enhanced Reactive Ion Etch (MERIE) system using a Dipole-Ring Magnet (DRM) is studied. It is capable of etching holes 40 μm in diameter in a Si substrate at etch rates as high as 50 μm/min. It was found that the Si etch reaction is dominated by the density of fluorine radicals, which is realized at high frequency and pressure. In holes with higher aspect ratios, it was found that the Si etch rate at the bottom of holes is determined not only by the supply of fluorine radicals, but is also influenced by an etch-inhibiting effect related to the sidewall of the hole. Using an 8 μm square mask, holes with straight sidewalls were etched to a depth of 60 μm at an etch rate of 24 μm/min.

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  Hitachi High-Technologies released a new dry plasma etcher designated as the Hitachi M-6180 and targeted for deep silicon trench etch. The new Hitachi M-6180 deep trench etcher provides for excellent uniformity, superior trench profiles, and high selectivity. The Hitachi M-6180 is based on an ECR (Electron Cyclotron Resonance) plasma source able to generate a high density (1×10¹¹ cm^-3) plasma at 0.01 Pa. The low temperature and low pressure reactions of the Hitachi M-6180 achieve superior trench profiles with no sidewall residue. The clean nature of the Hitachi M-6180 ECR etch chamber allows for Mean Time Between Wet Cleaning (MTBW) that is extremely long and particle levels that are very low.

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  NLD (magnetic Neutral Loop Discharge) plasma has two major characteristic features that high density one is generated at the lower pressure than 1 Pa and is controllable by changing the magnetic coil current. Utilizing this feature, ionic etching should be carried out at the lower pressure than 1 Pa for chemical reactive substrates, for example, organic materials or ArF photo resists, because ionic etching is low selective and low reactive.
  In Si etching process, the NLD plasma is utilized by employing sputter/etching method, which is scheduled cyclic. The NLD plasma is very stable for abrupt changing of the process pressure. This is brought on by weakly magnetized plasma. When PTFE (Poly Tetra-Fluoro-Ethylene) is used as a sputter target, deep etching of 180 μm is achieved for 7 μm pattern with aspect ratio of 25.7.

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  Deep Reactive Ion Etching^1-3) is well established as a commercial technique for forming Micro-Electro-Mechanical Systems (MEMS) devices. Over the last decade, development work has led to increases in silicon etch rate of an order of magnitude while requirements for etch depth uniformity and profile control have become more stringent as the wafer size has increased from 3 inch up to 200 mm.
  Many MEMS devices are still etched on 150 mm wafers, while most IC devices requiring Chip Scale Package (CSP) or other processing relating to Advanced Packaging will be manufactured on 200 mm wafers with planned moves to 300 mm wafers in progress or imminent.
  This paper describes the leading edge technology of Deep Si RIE including high rate etching and Through Silicon Vias (TSVs) hole formation on wafers up to 300 mm in diameter.

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  One-body type water- and air-cooling fixed masks made of forged 0.2% beryllium copper alloy have been developed, and successfully applied for the front end of a new undulator beamline, BL-13A, at the Photon Factory in Tsukuba, Japan. Advantages of the masks are a simple structure, no welding, low cost, high duration, and an extremely low out-gassing rate. Forged 0.2% beryllium copper alloy is demonstrated to be a valuable material for synchrotron radiation instruments.

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  Thin films were sputtered by an r.f. sputtering with a poly(etheretherketone) (PEEK) target at four different sputtering conditions e.g., 150 Watt (W)-0.6 Pascal (Pa), 25 W-0.6 Pa, 150 W-3.0 Pa and 25 W-3.0 Pa. Visible light transmissions of these sputtered thin films were measured with spectrophotometer. Elemental compositions and chemical bonding states of these sputtered thin films were analyzed with x-rays photoelectron spectroscopy (XPS) and fourier transform infrared spectroscopy (FT-IR). Surface morphologies of these sputtered thin films were observed with atomic force microscope (AFM). Molecular structures and elemental compositions of these sputtered thin films prepared with the r.f. sputtering were quite different from pristine PEEK. Oxygen contents of these thin films decreased compared to that of the pristine PEEK. Pressures during the sputtering give large effects on the molecular structure, elemental compositions and surface morphologies of these thin films.

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