New Products Enable High-Volume Manufacturing of 3D Devices
Applied Materials’ newest products, launched today, address some of the most difficult yet fundamental aspects of 3D device fabrication. The Applied Producer® XP Precision™ CVD system delivers exacting precision for depositing the films comprising the gate stack of 3D NAND memory devices; the Applied Reflexion® LK Prime™ takes industry-standard Reflexion LK technology to the more stringent levels of precision and defect reduction essential in 3D fabrication while also boosting productivity.
With the move from planar to 3D structures, critical dimension (CD) control challenges are transitioning from lithography to deposition and precision removal. In planar devices, lithography precision was the paramount requirement as CDs were measured in the horizontal plane. In 3D NAND devices, CDs are measured in the vertical plane, shifting those stringent requirements to deposition. In these multi-layer architectures, deposition uniformity is of the utmost importance because of the cumulative impact of propagating non-uniformity through the dozens of layers in the device. Each layer magnifies any error, affecting gate CD (thickness) variation. Maintaining precise and consistent thickness of the control gate and isolation layers is therefore essential for optimizing the speed and reliability of read/write performance.
The Producer XP Precision CVD system is designed to optimize the chamber environment and the interplay of process parameters, enabling it to deliver exceptionally uniform, ultra-thin, alternating layers of high-quality films with excellent process control. The extremely low defect counts of the deposition process are of vital importance in assuring the desired yield of high-end chips in which these 3D devices are used.
The next generation of 3D NAND requires further scaling, potentially doubling the number of cell layers, producing higher aspect ratio structures that require novel hard mask materials to withstand the long etch processes used to create these devices. The Precision CVD system enables deposition of thin hard mask films with high selectivity and low stress, making it easier to produce the next generation of 3D NAND.
While the XP Precision CVD system helps to build up 3D structures, the LK Prime CMP System offers new benchmarks in performance and productivity in removing and planarizing excess material and uniformly polishing each layer down to precisely the desired thickness. The importance of CMP in the manufacturing flow is growing as 3D device fabrication requires a greater number of steps. Logic 3D FinFETs involve up to 10 more planarization steps; 3D NAND require up to 5 more. The latter are especially long processes, making it harder to maintain a steady removal rate and achieve an ultra-uniform surface. Dividing them into several shorter steps yields superior results. The Reflexion LK Prime CMP platform makes this possible with double the capacity of the LK – six polish and eight cleaning stations. Moreover, more stations offer greater flexibility to run sequential, parallel, or batch processes and to increase throughput by up to 100 percent. Specialized polish heads, enhanced in-situ process controls, and a new pre-cleaning module contribute to the LK Prime system’s nanometer-scale control of these processes, helping to optimize device performance and yield.