U.S.-Brazil Cooperative Research on Plasma Processing of Semi-Conductors

该奖项支持喷气推进实验室的Santosh Sriastava、里约热内卢联邦大学的G.G.B.deSouza和A.C.de A.e Souza以及巴西圣卡洛斯联邦大学的I.IGA在半导体等离子体加工方面的合作研究。这三个小组将为低温等离子体沉积(半导体材料的蚀刻)中感兴趣的分子产生电子碰撞截面的补充数据。低密度等离子体沉积和刻蚀技术广泛应用于微电子领域。通常，这些等离子体中的气体压力是这样的：分子的数密度从10.9到10.12厘米-3不等，电子能量从1 eV到103伏不等。它们是高度非热的，主要是电子碰撞过程决定了它们的性质。因此，要模拟这些等离子体，准确了解几种不同类型的电子碰撞和光吸收截面是很重要的。为了表征与通过电子撞击当前感兴趣的分子而形成的离子有关的所有重要物理性质，必须知道在前一节中所讨论的离子形成的所有三个方面，即i)通过电子碰撞形成离子的截面的绝对值，ii)光电离截面和离子-离子重合，和iii)碎片离子的动能谱。在喷气推进实验室，提出者在测量从阈值到1keV的电子碰撞能量范围内的截面绝对值方面具有专业知识和仪器。在UFRJ，G.G.B.deSouza博士和A.C.de A.E.Souza博士已经为第二个方面的研究建立了技术和仪器。在UFSCAR，Ione Iga博士、Lee Iga博士和Jose Carlos Nogueira博士拥有测量碎片离子动能的仪器。因此，这三个小组的工作将是相辅相成的。一项合作努力已经产生了关于目前感兴趣的分子的重要数据，并将在未来继续这样做。

This award supports cooperative research on plasma processing of semi conductors as a collaborative research program between Santosh Srivastava of Jet Propulsion Laboratory, G. G. B. deSouza and A. C. de A. e Souza of the Federal University of Rio de Janeiro and I. Iga, of the Federal University of Sao Carlos (UFSCar), Brazil. The three groups will generate complementary data on the electron impact collision cross section for molecules of interest in the low temperature plasma deposition an etching of semi-conducting materials. The technique of low density plasma deposition and etching is used in the field of micro-electronics. Typically, gas pressures in these plasmas are such that number densities of molecules vary from 10.9 to 10.12 cm-3 and electron energies range from 1 ev to 10 3v. They are highly non-thermal and mainly the electron collision processes determine their character. Therefore, for modeling these plasmas an accurate knowledge of several different types of electron collision and photo-absorption cross section is important. In order to characterize all important physical properties related to ion formation by electron impact on molecules of present interest one has to know all three aspects of ion formation discussed in the previous section i.e. i) absolute values of cross sections for the ion formation by electron impact ii) photoionization cross sections and ion-ion coincidences, and iii) kinetic energy spectrum of fragment ions. At JPL the proposer has expertise and instrumentation for the measurement of absolute values of cross sections in the electron impact energy range from threshold to 1 KeV. At UFRJ Drs. G. G. B. deSouza and A. C. de A. e Souza have established techniques and instrumentation for the study of the second aspect. At UFSCar Drs. Ione Iga, Lee Mu Tao, and Jose Carlos Nogueira have instrumentation for the measurement of the kinetic energy of the fragment ions. Thus, the work performed by the three groups will be complimentary. A collaborative effort has already generated important data concerning molecules of present interest and will continue to do so in the future.