(August 24, 2010) — Applied Materials (NASDAQ:AMAT) released Eterna, a new flowable CVD (FCVD) technology. Ajay Bhatnagar, director, global product management in the Gap Fill Dielectric Division, explains in-depth how it differs from conventional CVD. The technology is run on AMAT’s Producer Eterna FCVD system. He also explains how it is being applied to new device architectures such as DRAM vertical transistors, NAND vertical bit stacks, and FinFETs.
Bhatnagar speaks with senior technical editor Debra Vogler.
The new dielectric film — which uses carbon-free precursors — is able to electrically isolate densely packed transistors in 20nm and below memory and logic chip designs and meets thermal budget requirements. The gaps between these transistors can have aspect ratios of more than 30:1 — five times higher than current requirements. The Eterna FCVD system’s process completely fills these gaps from the bottom up. The FCVD process also has a lower integrated process cost because as many as 20 or so purifying steps are eliminated.
Applied’s proprietary Eterna FCVD process delivers a liquid-like film that flows freely into virtually any structure shape to provide a bottom up, void-free fill. The Eterna FCVD system is installed at six customer sites for DRAM, Flash and Logic applications, where it is integrated on Applied’s benchmark Producer platform.
| Flowable CVD technology fills any structure, including high aspect ratio and reentrant features, with high-purity oxide. The true bottom-up deposition mechanism allows controllable film thickness, allowing both very thin layers and partial fill, enabling a wide range of applications and integration schemes. |
According to Bhatnagar, the company is targeting the replacement of spin-on dielectric (SOD) films as those films’ extendibility to advanced nodes is being questioned. In particular, Applied is targeting 3D memory architectures, which are in solid-state drives (SSDs) that are used in products such as iPads, netbooks, and even server farms. Other targeted memory applications are DRAM with buried bit-line and word-line architectures (e.g., 4F2). Looking ahead, Bhatnagar notes that end users are showing interest in applying the technology to defect defocusing in lithography and self-planarization films.
Adding to Bhatnagar’s comments, Bill McClintock, VP and GM of Applied’s DSM/ CMP2 Business Unit, said "The need to fill smaller and deeper structures in advanced chip designs creates a physical roadblock for existing deposition technologies. Applied has broken through this barrier today with the introduction of its new Eterna FCVD system – delivering the disruptive technology that can enable the continued progress of Moore’s Law."