| Atomic Layer Deposition(ALD), as an emerging thin film fabricating technology, can achieve good uniformity, controlled composition and step coverage by the characteristic of self-limiting growth. Temperature is one of the most important ALD parameters which will impact the stable growth of ALD process.The heating design and temperature distribution requirement for ALD chamber vary according to corresponding applications. This thesis researches temperature distributions and control methods of three different types ALD chamber, and optimizes the chamber design. The main works of this thesis includes:(1) This thesis proposes an optimized chamber to avoid deformation of inside surface. Chamber inside surface needs good flatness for planar substrate to avoid large temperature gradient. By heat treating and groove design, the chamber can avoid excess deformation on inside surface.(2) Alternating into isotropic heating can achieve high temperature uniformity in the zone of powder substrate. Radiation is the main way of heat transfer for powder substrate. A chamber with only heaters in top and bottom surface has the largest temperature difference of 16 ?, which is beyond the requirement of ALD temperature window. By altering peripheral heated, the zone temperature difference can be reduced to 5?.(3) By inlet heating compensation, substrate surface temperature fluctuation can be alleviated for spatially separated ALD. Spatially separated ALD is modularized designed, and smaller dimensions for structure should be choosed for less temperature fluctuation. Substrate surface temperature fluctuation can be controlled within 3? with better thin film surface quality by inlet temperature compensation.(4) The paper makes heating designs for different types of substrate. Heat conduction is the main way of heat transfer for planar substrate chamber and spatial ALD, and radiation for powder substrate. Corresponding control methods have been proposed to achieve temperature and deposition uniformity.. |
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