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Product Briefing Outline: Applied Materials has started a major effort to enable the widespread adoption of through-silicon vias (TSVs), to boost chip performance and functionality in a smaller area. Its ‘Applied Centura Silvia Etch’ system, targets the need for high-performance, low-cost, TSV applications. The Silvia system’s profile control enables the smooth, vertical via sidewalls that are critical for the subsequent deposition of high-quality liner and fill films. The highly flexible Silvia system can etch both silicon and oxide in the same chamber for established and emerging TSV integration schemes.

Problem: In the drive to maximize the functionality-to-volume ratio, device makers are integrating chips using three-dimensional (3D) schemes. Through-Silicon Via (TSV) technology enables 3D interconnects by creating vertical pathways functioning as components of the integrated circuit to connect stacked chips or wafers avoiding the cost, space and performance issues associated with combining multiple functions on one chip.  However, deep silicon etch processing is challenging due to multiple etch steps, which can represent a significant portion (20%) of the total cost, when high quality, low cost, volume manufacturing is required.

Solution: The Silvia uses Applied’s proprietary time-multiplexed gas modulation (TMGM) process. While conventional TMGM processes etch vias with heavily scalloped sidewalls that are difficult to fill, the Silvia system is claimed to achieve smooth, vertical profiles at the rapid etch rates required for high productivity manufacturing. The Silvia system’s profile control accommodates a broad range of TSV schemes, each with different challenges. In the via-first scheme, the system provides the required profile control and high selectivity to photoresist for etching very small, deep holes with very smooth sidewalls. The handles via-last schemes, where cost of ownership (COO) is critical. It is claimed to be the only TSV etch system to overcome the tradeoff between profile control and high etch rate faced by conventional methods, while its consumables-free process kit minimizes the cost of consumables (CoC).

Applications: TSV etching of three-dimensional (3D) IC’s.

Platform: There are several approaches to TSV implementation. Applied has the 300mm systems and processes required for the majority of TSV manufacturing steps, including mask, etch, film deposition and CMP technologies. To accelerate mainstream adoption, Applied is working with other equipment suppliers, such as Semitool, Inc. and wafer bonders, to fully characterize inter-process dependencies while lowering overall costs.

Availability: December 2008 onwards.