Market demand for faster, smaller, more powerful, and energy-efficient electronics is driving the development of new fabrication strategies that enable producing advanced devices with fine, closely packed features and complex 3D structures. Creating the cutting-edge microprocessors, memory devices, and numerous other product types in demand today is extremely challenging and requires continuous innovation to deliver capable processing solutions.
Through collaboration and drawing on multiple areas of expertise, Lam continues to develop the new capabilities required to manufacture these increasingly challenging devices. Our innovative technology and productivity solutions deliver a wide range of wafer processing capabilities needed to create the latest chips and applications – from transistor, interconnect, patterning, advanced memory, and packaging to sensors and transducers, analog and mixed signal, discretes and power devices, and optoelectronics and photonics.
Transistors – the “brains” of a chip – are tiny switches that control the flow of electricity, and there can literally be billions of these on a single integrated circuit. Demand for smaller, more powerful electronics is driving the development of new transistor architectures like 3D FinFET designs and the use of specialty materials such as high-k/metal gates. These in turn allow continued shrinking of device feature sizes. With dimensions for the latest transistors now at the atomic level, they are extremely challenging to manufacture. To ensure the high performance expected of these advanced devices, manufacturing capabilities that deliver exceptional precision and control in forming the tiny features are needed.
The interconnect makes up the intricate wiring that connects the billions of individual components (transistors, capacitors, etc.) on a chip. As smaller and smaller devices are packed closer together, more interconnect levels are needed, and connecting everything becomes increasingly challenging. In fact, as the shrinking of feature dimensions has continued, interconnects are now becoming the speed bottleneck in today’s most advanced chips. As a result, techniques that minimize resistance of the metal connections and novel dielectric materials that boost insulating capacity are needed. To produce the latest high-performance electronic devices, advanced interconnect structures involve narrow geometries and complex film layers, which require increasingly flexible and precise process capabilities.
Patterning involves the set of process steps – including lithography, deposition, and etch – that create the extremely small, intricate features of an integrated circuit. With each new generation, device dimensions continue to shrink. For advanced structures, these feature sizes can be too small and/or packed too closely together for conventional lithography, the step that transfers the chip design’s intricate detail from the mask “template” onto the wafer. To compensate, chipmakers are using advanced techniques like double/quadruple and spacer-based patterning, involving multiple masks and process sets. Even as these approaches ease lithography limitations, they create new demands for exceptional process precision and film quality in order to accurately produce the fine, dense features required.
Memory cells – the chip components that store electronic data – include short-term volatile (such as DRAM) and long-term non-volatile (such as flash) storage types. DRAM is the mainstay for “working” (active) memory, while flash memory is used to store large amounts of data in a compact form. To increase device density for more storage capacity, DRAM features continue to shrink, and NAND flash has moved to 3D architectures, which raise additional processing challenges. For example, the numerous layers in 3D NAND are vulnerable to stress, and any imperfections in the high aspect-ratio channels can create electrical shorts and interference. Production of newer memory types that bridge the gap between active and storage classes is also difficult due to the use of novel, hard-to-process materials. As a result, exceptional process control, flexibility, and productivity are needed.
Packaging refers to the process steps that form the protective enclosure around a finished chip and create the external connections for input/output. Consumer demand for smaller, faster, and more powerful mobile electronics is driving the development of alternate packaging approaches. Strategies include wafer-level packaging – where chips are packaged while still on the wafer, then separated – using bumping, redistribution layers, and fan-out packaging approaches. Another technique is the use of through-silicon vias (TSVs), which are conductive pillars of metal that connect stacks of chips. These strategies generate multiple challenges for the processing steps involved, such as managing a range of feature shapes, multiple material types, and strict thermal budgets.
SENSORS & TRANSDUCERS
Transducers are devices that change some type of energy – such as light, motion, heat, or a chemical reaction – from one form into another. For example, actuators are a type of transducer that convert energy into motion. When the output of a transducer converts the energy to a readable format (an analog or digital representation), it is called a sensor. Many types of transducers and sensors are used to convert and measure signals generated in the environment all around us, and their applications continue to grow. While producing these devices does not necessarily require the latest generations of processing equipment, it does require the development of processes to support many unique device designs. Also, some of the fabrication steps involve materials not used in other device types, such as piezoelectric thin films. As a result, equipment technical capability, reliability, productivity, and overall cost-effectiveness are critical.
ANALOG & MIXED SIGNAL
Analog electronics are devices with a continuous variable signal, while digital electronics provide discrete signals and differentiate only two levels (such as “on” and “off”). As the name implies, mixed-signal devices contain both analog and digital circuits. Mixed-signal designs are cost-effective solutions commonly used to build consumer electronics applications, and this category has seen dramatic growth with the increased use of smartphones and other portable technologies. Processing equipment that provides high reliability and productivity cost-effectively is needed for the economical manufacture of analog and mixed-signal devices.
DISCRETES & POWER DEVICES
Discrete devices are single semiconductors like diodes or transistors. Power transistors are an important class of discrete devices and are used in a range of applications to regulate voltages, help lower power consumption, and reduce heat generation. For example, they are essential components in circuits aimed at extending battery life in portable electronics. Emerging wide-bandgap power devices (e.g., GaN and SiC) offer both low- and high-power applications at higher frequencies, addressing consumer electronics as well as higher-power applications in the power grid, energy, transportation, and automotive sectors. Examples of key power devices based upon silicon or wide-bandgap materials include power diodes, thyristors, power metal-oxide semiconductor field effect transistors (MOSFETs), and insulated gate bipolar transistors (IGBTs). These types of devices require low-cost manufacturing from reliable, high-productivity, and cost-effective equipment.
OPTOELECTRONICS & PHOTONICS
A photonic integrated circuit (PIC), also known as an integrated optical circuit, is similar to an electronic integrated circuit. However, instead of using only electrical signals to transmit information, these optoelectronic devices use both electrical and optical (light) signals. The use of optics enables more bandwidth and faster connectivity while reducing power costs. Optical components are well established in telecommunications and are technologies that provide connectivity for homes. The growth in data center applications has greatly increased demand for PICs since they enable more efficient system architectures, significantly reduce energy consumption, and improve performance. As such, the use of optoelectronic systems is expected to continue growing and requires cost-effective, reliable manufacturing solutions.