CMP Pad Selection for 28nm Node and Beyond

July 07,2015

Chemical-mechanical planarization (CMP) processes and applications have been vital for high-volume manufacturing (HVM) of complementary metal-oxide semiconductor (CMOS) integrated circuits (ICs) for decades, and Dow Electronic Materials has been supplying critical CMP consumable materials to the industry for over 20 years. Starting with the IC1000™ family of CMP pads (the latest of which is the IC1010™), and including the SUBA™ and VISIONPAD™ families, the latest family of offerings is within the IKONIC™ brand name.

The IKONIC polishing pad platform is a portfolio expansion that brings to market Dow's most advanced technology in a range of soft and hard polishing pads that target multiple CMP applications in device manufacturing. The IKONIC platform offers a series of softer (and hard) pads designed to deliver high performance levels for a broad range of CMP applications at or below the 28nm technology node, including copper, tungsten, inter-layer dielectric (ILD), and shallow trench isolation (STI).

Before the IKONIC platform, CMP pads such as the industry leading VISIONPAD (VP5000/VP6000) were fixed formulations with given mechanical properties and morphologies. Now, with the IKONIC platform, we have the ability to fine-tune the hardness levels and the porosity of the pads in harmony with a given slurry set, allowing for easy conditioning and thus optimized texture for multiple applications.

The IKONIC 2000 pads are designed for processes needing soft and ultra-soft pads, such as for copper barrier-layer planarization. The IKONIC 3000 pads are designed for processes needing medium hardness pads, such as for bulk copper removal. The IKONIC 4000 pads are designed for processes needing relatively hard pads, such as for STI and transistor gate formation.

As we move below the 28nm node, the transition to 450mm wafers becomes a consideration. Although there is no volume demand at this time for 450mm wafer processing, Dow has invested in 450mm manufacturing capability to be able to make these pads. Because Dow has deep experience with polymer chemistry and processing, Dow is able to physically scale the pad diameter from 300mm to 450mm while maintaining uniformity of both material composition and macro-structure. Additionally, IKONIC 4000 CMP pads have been designed to maximize global uniformity across the wafer surface, so Dow believes that process results on 300mm wafers can scale properly to 450mm wafers if or when the industry demands the larger substrates.

The “one-size-fits-all” approach to CMP processing is no longer viable; a tunable platform of products is required to meet our customers' ever-evolving and more technically challenging manufacturing needs. The IKONIC CMP pad platform is uniquely positioned to address future IC fabrication requirements because of the tunability of its materials properties.

Dow's understanding of polymer science in general and specific expertise in developing CMP solutions helps our customers to produce next-generation devices. Our customers' requirements for lower defectivity and improved cost-of-ownership will continue to drive the focus of our research programs moving forward.

The IKONIC CMP pad platform draws on the company's expertise in materials science, planarization, manufacturing, and high-volume supply. These capabilities, combined with collaborative customer relationships, make Dow a global leader in CMP pad technology.

The IKONIC 2000 pads are designed for processes needing soft and ultra-soft pads, such as for copper barrier-layer planarization. The IKONIC 3000 pads are designed for processes needing medium hardness pads, such as for bulk copper removal. The IKONIC 4000 pads are designed for processes needing relatively hard pads, such as for STI and transistor gate formation.

As we move below the 28nm node, the transition to 450mm wafers becomes a consideration. Although there is no volume demand at this time for 450mm wafer processing, Dow has invested in 450mm manufacturing capability to be able to make these pads. Because Dow has deep experience with polymer chemistry and processing, Dow is able to physically scale the pad diameter from 300mm to 450mm while maintaining uniformity of both material composition and macro-structure. Additionally, IKONIC 4000 CMP pads have been designed to maximize global uniformity across the wafer surface, so Dow believes that process results on 300mm wafers can scale properly to 450mm wafers if or when the industry demands the larger substrates.

The “one-size-fits-all” approach to CMP processing is no longer viable; a tunable platform of products is required to meet our customers' ever-evolving and more technically challenging manufacturing needs. The IKONIC CMP pad platform is uniquely positioned to address future IC fabrication requirements because of the tunability of its materials properties.

Dow's understanding of polymer science in general and specific expertise in developing CMP solutions helps our customers to produce next-generation devices. Our customers' requirements for lower defectivity and improved cost-of-ownership will continue to drive the focus of our research programs moving forward.

The IKONIC CMP pad platform draws on the company's expertise in materials science, planarization, manufacturing, and high-volume supply. These capabilities, combined with collaborative customer relationships, make Dow a global leader in CMP pad technology.