Development of Stacked Thin-film Micro-actuator with Two Laser Beam

设计并研制了一种结合分子束外延和ArF准分子激光磨损的超薄多层成膜装置。采用高温Knudsen电池作为蒸发源，对沉积速率和成分进行了精确控制。最高升温温度为1700℃。为了校正金属氧化物陶瓷膜的氧含量，并对基板表面进行清洁处理，安装了离子束枪。将CO_2激光束照射到基体表面进行加热和活化。采用ArF准分子激光在Si（100）衬底上制备了厚度为4 ~ 6 nm的A1_20_3、PbO、TiO_2、BaTiO_3等金属氧化物陶瓷薄膜。在室温下成功沉积极薄、极细的Al_2O_3薄膜是可能的。x射线衍射分析表明，在室温下形成的薄膜的晶体结构是无定形的，而在750℃以上形成的薄膜则转变为γ结构。表面粗糙度小于0.72 nm R_y， AFM观察未发现任何孔洞和微缺陷。该超薄薄膜可用于多层GMR器件的薄膜绝缘体、约瑟夫森结等。对申请的调查应继续进行。结果表明，激光磨损过程中PbO、TiO_2、BaTiO_3薄膜的晶体结构受衬底温度的控制。在400℃以上，PbO膜逐渐由α结构转变为β结构。在450 ~ 550ºC的温度下，BaTiO_3薄膜呈现钙钛矿结构，而在600ºC以上的温度下，Ba发生分解，薄膜转变为金红石型TiO_2结构。结果表明，ArF准分子激光研磨可形成BaTiO_3和TiO_2-PbO多层铁电薄膜。我们形成了各种Fe， Ni, Ti, TiNi（形状记忆合金；SMA）薄膜。Fe_<65>Ni_<35> （invar合金：IVA）。得到的最小沉积速率小于0.01 nm/min。合金成分控制在1%以下。我们设计了一种新型的SMA薄膜驱动器，它是由两层薄薄的Fe和IVA组成的SMA和双金属堆叠而成。该驱动器可以通过双金属变形力恢复初始形状。我们正在研究动态特性和最佳形状或尺寸。少

A new ultra-thin multi-layr film forming apparatus combined molecular beam epitaxy and ArF excimer laser abrasion was designed and developed. As an evaporating source, high temperature Knudsen cell was employed to control of depositing rate and constituents precisely. The maximun rising temperature was 1700ﾟC.In order to correct the oxygen content of a metal oxide ceramics film and to treat the surface of a substrate clean an Ion-beam gun was installed. And for heating and activating, CO_2 laser beam was irradiated onto the substrate surface.The metal oxide ceramics such as A1_20_3, PbO,TiO_2, BaTiO_3 films of 4-6 nm thickness were fomed on Si (100) substrates by ArF excimer laser abrasion. It is possible to deposit the extremely thin and fine Al_2O_3 film at room temperature successfully. According to X-ray diffraction analysis, the crystallographic structure of the film formed at room temperature was amorphous, but it changed to gamma structure above 750ﾟC.Surface roughness was less … More 0.72 nm R_y and any hole or micro-defect wasn't found by the AFM observation. This ultra-thin film would be applicable for the film insulator of multi-layr GMR devices, Josephson junction etc. The investigation into applications should be continued. It was found that crystallographic structure of the PbO,TiO_2, BaTiO_3 films were controlled by temperature of the substrate during laser abrasion. The PbO film changed from alpha to beta structure beyond 400ﾟC gradually. The BaTiO_3 film shows the perovskite structure at the temperature between 450 and 550ﾟC,however, Ba decomposes then the film changes rutile type structure TiO_2 at the temperature above 600ﾟC.It was found that the ferroelectrics thin film of BaTiO_3 and TiO_2-PbO multi-layr can be formed by ArF excimer laser abrasion.We formed various thin film of Fe, Ni, Ti, TiNi (shape memory alloy ; SMA). Fe_<65>Ni_<35> (invar alloy : IVA). The minimum depositing rate obtained was less than 0.01 nm/min. Constituents of alloys were controlled better than 1%. We designed a new SMA film actuator which was stacked SMA and bimetal consisting two thin layrs of Fe and IVA.The actuator is possible to recover initial shape by bimetal defoming force. We are investigating the dynamic characteristics and optimum shape or size. Less