Ana R. Londergan

Thin film atomic layer deposition equipment for semiconductor processing

Abstract Atomic layer deposition (ALD) of ultrathin high-K dielectric films has recently penetrated research and development lines of several major memory and logic manufacturers due to the promise of unprecedented control of thickness, uniformity, quality and material properties. LYNX-ALD technology from Genus, currently at beta phase, was designed around the anticipation that future ultrathin materials are likely to be binary, ternary or quaternary alloys or nanolaminate composites. A unique chemical delivery system enables synergy between traditional, production-proven low pressure chemical vapor deposition (LPCVD) technology and atomic layer deposition (ALD) controlled by sequential surface reactions. Source chemicals from gas, liquid or solid precursors are delivered to impinge on reactive surfaces where self-limiting surface reactions yield film growth with layer-by-layer control. Surfaces are made reactive by the self-limiting reactions, by surface species manipulation, or both. The substrate is exposed to one reactant at a time to suppress possible chemical vapor deposition (CVD) contribution to the film. Precisely controlled composite materials with multiple-component dielectric and metal–nitride films can be deposited by ALD techniques. The research community has demonstrated these capabilities during the past decade. Accordingly, ALD equipment for semiconductor processing is unanimously in high demand. However, mainstream device manufacturers still criticize ALD to be non-viable for Semiconductor device processing. This article presents a broad set of data proving feasibility of ALD technology for semiconductor device processing.

Mass production worthy HfO/sub 2/-Al/sub 2/O/sub 3/ laminate capacitor technology using Hf liquid precursor for sub-100 nm DRAMs

For the first time, we successfully demonstrated MIS capacitor with ALD (Atomic Layer Deposition) grown HfO/sub 2/-Al/sub 2/O/sub 3/ laminate film using Hf liquid precursor (Hf(NEtMe)/sub 4/) with EOT of 22.5 /spl Aring/ and acceptable leakage currents (1.0 fA/cell at 1.65 V) which is comparable to the smallest reported value. Advantages of Hf(NEtMe)/sub 4/ liquid precursor for DRAM capacitor dielectric are excellent step coverage (94% on high aspect ratio(>40:1)) and reasonable throughput (over two times higher than that of HfCl/sub 4/ solid precursor). This study will provide practical solution for chip-making industry in terms of mass production worthy process for sub-100 nm DRAM capacitor.