DEVELOPMENT OF DUAL-FREQUENCY EXCITATION, LOW-KINETIC-ENERGY PARTICLE PROCESS EQUIPMENT

开发了新的工艺设备和利用这些设备的新工艺技术。因此，低温形成具有理想界面特性的高质量薄膜，这是超大规模集成（ULSI）的最基本要求。两个不同频率的射频功率输入被提供给目标电极和晶圆支架电极，控制在电极间区域产生的Ar等离子体。这使我们能够非常精确地控制最重要的薄膜生长参数，如薄膜生长速率，表面激活离子轰击能量和通量。此外，新设计的屏蔽电极的引入降低了等离子体电位，从而消除了由于腔室材料溅射造成的污染。薄膜生长新工艺技术的应用揭示了许多有趣和重要的特征，如下所述。硅外延的生长温度已经降低到250℃以下。在这个低温下，掺杂剂完全激活，以及性能优异的器件的制造已经被实验证明。将该工艺应用于Cu薄膜的形成，成功地在SiO_2表面生成了几乎单晶的Cu互连图案。此外，在没有任何合金化热循环的情况下，验证了理想金属/半导体接触特性的形成。该工艺在铝互连层中的应用也非常成功。在没有任何合金热循环的情况下，建立了非常低的Al- N^+硅接触电阻。通过优化离子轰击条件，可以在500℃的退火温度下完全抑制小丘的形成。在高宽高比触点/通孔处，使用针对丘抑制优化的相同离子轰击条件实现了优异的再填充特性。因此，该工艺和设备非常适合应用于深亚微米ULSI制造。少

New process equipment as well as new process technologies utilizing the equipment has been developed. As a result, low temperature formation of high quality thin films with ideal interface characteristics, the most essential requirement for ultralarge scale integration (ULSI), has been established. RF power inputs with two different frequencies were supplied to the target and wafer-holder electrodes, controlling the Ar plasma created in the interelectrode region. This has enabled us to control the most important thin film growth parameters, such as film growth rate, surface activating ion bombardment energy and flux, in a very accurate manner. Furthermore, introduction of a newly designed shielding electrode reduces the plasma potential, thus eliminating the contamination due to the chamber material sputtering. Application of the new process technology for thin film growth has revealed a number of interesting and important features as described below. The silicon epitaxial growth tempe … More rature has been reduced to as low as 250ﾟC. Complete dopant activation at this low temperature, as well as the fabrication of devices with excellent performance have been experimentally demonstrated. When the process was applied to the formation of Cu thin films, we have succeeded to produce almost-single crystal Cu interconnect patterns on the SiO_2 surface. In addition, the formation of ideal metal/semiconductor contact characteristics were verified without any alloying beat cycles. Application of the process to aluminum interconnect formation was also very successful. A very low Al- N^+ silicon contact resistance is established without any alloying heat cycles. Complete suppression of hillock formation up to 500ﾟC annealing temperature is possible by optimizing the ion bombardment condition. Excellent refill characteristics at high aspect-ratio contacts/vias are realized using the identical ion bombardment condition optimized for hillock suppression. As a result, the process and the equipment is ideal for application to deep-submicron ULSI fabrication. Less