Providing precision control at the atomic scale
Semiconductor processes used in the manufacture of today’s most advanced chips are challenged to literally push the limits of physics and chemistry with their nanoscale features, novel materials, and increasingly complex 3D structures. Meeting the ever-changing fabrication demands of new chip designs requires precision control at the atomic scale.
To ensure those new process technologies are production-ready when new chips head to the fab, Lam’s scientists and engineers stay abreast of our customers’ manufacturing needs. Our broad portfolio of market-leading products for thin film deposition, plasma etch, photoresist strip, and wafer cleaning are complementary processing steps used throughout semiconductor manufacturing. To support advanced process monitoring and control of critical steps, our product offerings include a line of high-precision mass metrology systems.
Deposition processes create layers of dielectric (insulating) and metal (conducting) materials used to build a semiconductor device. Depending on the type of material and structure being made, different techniques are employed. Electrochemical deposition (ECD) creates the copper “wiring” (interconnect) that links devices in an integrated circuit. Metal plating of copper and other metals is also used for through-silicon vias and wafer-level packaging applications. Tiny tungsten connectors and thin barriers are made with the precision of chemical vapor deposition (CVD) and atomic layer deposition (ALD), which adds only a few layers of atoms at a time. Plasma-enhanced CVD (PECVD), high-density plasma CVD (HDP-CVD), and ALD are used to form the critical insulating layers that isolate and protect all of these electrical structures.
For the numerous materials and demanding features involved, Lam’s thin film deposition products provide the precision, performance, and flexibility needed for a wide range of challenging device applications.
Etch processes help create chip features by selectively removing both dielectric (insulating) and metal (conducting) materials that have been added during deposition. These processes involve fabricating increasingly small, complex, and tall and narrow features using many types of materials. The primary technology, reactive ion etch (RIE), bombards the wafer surface with ions (charged particles) to remove material. For the tiniest features, atomic layer etching (ALE) removes a few atomic layers of material at a time. While conductor etch processes precisely shape critical electrical components like transistors, dielectric etch forms the insulating structures that protect conducting parts. Etch processes also create the tall, column-like features used, for example, in TSVs that link chips together and in micro-electromechanical systems (MEMS).
Lam’s plasma etch systems deliver the high-performance, high-productivity capabilities needed to form exacting structures – whether tall and narrow, short and wide, or measured in only a few nanometers.
STRIP & CLEAN
Strip and clean techniques are used between manufacturing steps to eliminate unwanted material that could later lead to defects and to prepare the wafer surface for subsequent processing. Photoresist strip removes the photoresist film and residues following ion implant or etch steps. To clear away particles, contaminants, residues, and other unwanted materials, wafer cleaning steps are inserted throughout manufacturing. Wet processing technologies can be used for wafer cleaning as well as strip and etch applications. Plasma bevel cleaning is used to enhance die yield by removing unwanted materials from the wafer’s edge that could impact the device area.
Lam’s strip technologies selectively remove remaining photoresist and provide process flexibility for multiple applications, while our high-productivity clean products deliver pristine surfaces center to edge for the most demanding cleaning steps.
Mass metrology measures the change in mass following deposition, etch, and clean processes to enable monitoring and control of these often-repeated core manufacturing steps. For design components like thin film stacks, high aspect-ratio structures, and complex 3D architectures, optical techniques are limited in their ability to measure accurately the thick, deep, or otherwise visually obscured features. Measuring the change in mass for these applications provides a straightforward high-precision solution for monitoring and control of the critical features in advanced device structures, where there is often little tolerance for variation.
Lam’s line of high-precision mass metrology systems provide in-line monitoring and control of deposition, etch, and clean steps in real time – recording minute changes in mass to enable advanced detection of potential process excursions.