Enabling Thermal Processing of High and Low Dielectric Constant Materials

ABSTRACTThe focus of ULSI electronics is shifting rapidly towards the development and integration of various low and high dielectric constant materials. Memory manufacturers are driving the quest for integration-friendly, high dielectric constant materials, while the logic makers are seeking materials with the lowest possible dielectric constant to use as interlayer dielectrics for their multilayer backend needs. Both of these categories of materials need the highest possible level of reliability, integrability, and manufacturability in the current and upcoming real world. Strong development emphasis in improving the structural aspects of these materials is needed more now than ever before both in university laboratories and industrial R&D. An intense focus on these materials demands immediate, improved, and innovative process solutions. One key process area is the thermal engineering and processing of these materials and hence is the focus of this paper.In this paper, we present recent results from both university and industry process development work. We compare and contrast the thermal process requirements of some enabling materials with dielectric constants ranging from 2 to more than 100. The examples in our study encompass materials such as Teflon™, PLZT, cell nitride, and tantalum pentoxide. The enhancements in the structural and electrical performance of these materials as a function of thermal cycles used either for deposition or annealing is demonstrated through various examples.