MEMS

While there are numerous applications of dry etch processes in MEMS, the deep silicon etch requirements of freely movable, capacitively coupled MEMS such as those used for inertial measurement, pose the greatest process challenges. Accurate and repeatable profile control across the wafer, fast etch rate and high device yield are principal requirements for today’s critical MEMS etch processes.

Applied Centura DPS DT+ Etch

The  DPS DT+ etch system is a production proven deep reactive ion etch (DRIE) technology delivering a high degree of process uniformity and control, combined with unmatched reliability. Requiring no dry clean between wafers, the DPS DT+ is capable of delivering high productivity whilst maintaining excellent particle performance in the most demanding production environments.

With more than 5,000 systems installed worldwide, the Centura Platform delivers a high level of productivity with a low total cost-of-ownership. Supporting 150mm and 200mm wafer sizes, the Centura platform can accommodate up to four DPS DT+ DRIE chambers for high volume manufacturing.

Traditional approaches using wet chemistry are effective, however stiction effects from liquid trapped beneath the structure can prevent complete release, leading to non-functional mechanisms. Instead, Applied utilizes vapor phase technology to eliminate stiction and greatly improve device yields.

Applied Semitool HF Vapor Etch

The Semitool HF Vapor etch system is capable of releasing MEMS devices by removing sacrificial layers surrounding mechanical elements. Based on an isopropyl alcohol and hydrogen fluoride chemistry, the system delivers excellent uniformity, both within-wafer and from wafer to wafer, while preventing damage to the surrounding materials – essential for reliable MEMS device function.

The HF Vapor release etch system is based on the Semitool spray acid platform, proven in over 750 customer installations worldwide. The highly-flexible substrate handling system can accommodate a wide range of wafer sizes up to 200mm as well as individual die. With excellent particle control and repeatable etch performance, the Semitool HF Vapor etch system is an excellent choice for cost-effective MEMS device release and other selective oxide removal processes.

Since the early 1990s, Applied Materials has led the semiconductor dielectric deposition market with its single-wafer chemical vapor deposition (CVD) technologies. Applied has worked with its partners to adapt these technologies to applications high-volume MEMS manufacturing.

Applied Materials is engaged in continued development to deliver material solutions to meet the stringent fabrication requirements of MEMS, including, thick films, engineered stress layers, low temperature, CMOS compatible films and films for harsh environments.

	Applied Centura DxZ CVD Regarded as the industry’s leading single-wafer CVD chamber, the DxZ chamber technology has a proven track-record with over 25 million wafers processed in dielectric PECVD applications. The high-productivity Centura platform, which offers the flexibility to handle 150mm and 200mm wafers, can support up to four single wafer process chambers.
	Applied Producer DxZ CVD For the highest available wafer throughput, the production-proven DxZ dielectric deposition technology is also available on Applied’s high productivity Producer platform. Capable of processing six wafers simultaneously in paired reactors, the Producer platform can deliver the MEMS industry’s lowest cost-per-wafer for dielectric deposition applications.
	Applied Centura LPCVD  Low Pressure Chemical Vapor Deposition (LPCVD) chambers offer uniform deposition of undoped, in-situ doped poly silicon, Silicon Nitride and High Temp Oxide (HTO) films with excellent repeatable performance. The Centura LPCVD system combines the advantages of single-wafer speed, control and flexibility to satisfy the increasingly difficult demands of advanced MEMS applications.

The ability to deposit a wide variety of ultra-pure films is key to the fabrication of many MEM devices today. From thick metal layers used in high power applications to highly uniform piezo-electric layers used for communications – the requirement to deposit metal-based material layers with tight control over film thickness has evolved well beyond reflector layers traditionally used in optical MEMS.

Applied Endura

MEMS fabrication requires the depostion of a wide range of materials using PVD technology, such as AlN for RF devices and Al for mechanical switches and barrier films.

Using the Endura platform, the leading semiconductor metallization platform since its launch in 1990, Applied has developed proven processes for depositing the complete range of materials used in MEMs devices today.

The Endura system's industry-leading PVD technology delivers highly uniform, highly conformal films with tunable stress. Delivering the most efficient raw material usage, and the highest throughput and reliability available today, the Endura platform from Applied Materials is the right choice for MEMS PVD.

As MEMS device complexity increases, the number of levels is also increasing, placing new demands on the ability of CMP technology to optimize planarity performance across the wafer for materials with very different mechanical properties, while achieving rapid removal rates to maximize productivity and drive down costs.

Applied Materials continues to develop CMP solutions for enhanced productivity in high-volume MEMS manufacturing, offering MEMS device makers proven solutions with unmatched reliability and on-wafer performance.

Applied Mirra Plus CMP

The production-proven Mirra Plus CMP system is ideally suited for the high volume production of MEMS devices. The proprietary Titan polishing head technology features five-zone downforce control combined with advanced endpoint solutions to delivers best-of-breed process performance to maximize device yield.

With an installed base of more than 1800 systems, the Mirra platform delivers high productivity by maximizing throughput while minimizing cost-of-ownership and cost-of-consumables. Supporting both 150mm and 200mm wafer sizes, the flexible Mirra architecture’s three polishing stations enable a wide range of MEMS planarization applications.

Epitaxially-deposited films of single- and poly-crystalline Si, Ge and SiGe are widely used for structural and sacrificial films in MEMS applications.

Reduced pressure processing is utilized in many semiconductor applications from traditional bipolar and BiCMOS processing to more advanced low temperature applications. The Epi Centura offers superior temperature, pressure and gas flow control for different process requirements in the semiconductor industry as well as other applications such as MEMS.

Applied Centura Epi RP

The Centura Epi RP system is a production-proven, single-wafer, multi-chamber epitaxial silicon deposition system with worldwide installations. Each radiantly-heated process chamber provides precise and repeatable control of deposition conditions, ensuring superior film quality. The wide range of temperatures and pressures and the excellent temperature uniformity of the Centura Epi system enable advanced low temperature epitaxial and polycrystalline deposition processes such as germanium and silicon-germanium that are used in many MEMS structures.

In addition to aspect ratios approaching 100:1 and micrometer-scale critical dimensions, Applied Material’s inspection, review and metrology systems have demonstrated the ability to characterize wafer centre-to-edge effects like sidewall tilt, roughness and mask undercut, which are critical elements that impact device yield.

With advanced capabilities such as tilted electron beam imaging, laser-based inspection and in-situ material analysis, Applied’s suite of metrology tools offer customers early identification of process excursions, drive yield improvement and decrease the cycle time for new product development.

	Applied VeritySEM Metrology The fully-automated VeritySEM metrology solution offers advanced features such as tilt imaging, 3D measurements, sidewall angle and roughness analysis to help MEMS manufacturers perform critical dimension measurement at very high SEM resolution while maintaining high throughput and low cost of ownership. With over 500 systems installed world wide, the VeritySEM platform supports 150mm, 200mm and 300mm wafer sizes with multiple substrate handling options.
	Applied SEMVision Defect Analysis With over 750 systems installed world wide the SEMVision is the market leader in inline defect review. The system’s high speed enables MEMS device makers to make defect review and integral part of the manufacturing process, instead of relying on time-consuming off-line measurements. The platform includes advanced capabilities to speed root cause analysis such as in-situ material analysis, tilt up to 45 degrees, 360° rotation, side wall SEM imaging and ion-beam cross sectioning. The system supports 200mm and 300mm wafer size with multiple factory interface handling options.
	Applied ComPASS Inspection Applied’s laser-based wafer inspection systems deliver high sensitivity defect detection with fast inspection speed to provide in-line yield enhancement support. The system supports inspection applications at all stages of MEMS manufacturing with capabilities such as tilt and normal incident laser scan, automatic defect classification, polarization control, particle and pattern defect detection. The ComPASS platform supports 150mm, 200mm and 300mm wafer size with multiple factory interface handling options.

MEMS functionality can also be increased by integrating additional wafer materials onto the wafer during the fabrication process. This practice introduces a new level of complexity to the MEMS fabrication process flow, placing new demands on the precision and repeatability of bonding technology.

Applied Materials provides global distribution and support services for the systems manufactured by Applied Microengineering Ltd. (AML), world leaders in wafer bonding machines and bonding services.

AML FAB12 Wafer Bonder The FAB12 wafer bonder can join together two substrates with 2μm accuracy using a wide range of bonding methods, including: Adhesive Anodic Direct (high and low temperature) Eutectic Glass Frit Solder Thermo-compression.

Unlike competing systems, the substrates are only aligned and brought into contact after preheating in a vacuum chamber – key to achieving optimum repeatability and accuracy. For more information on the system's key functions, click here.