Brad Stimson & Alan Ritchie, Applied Materials, Inc., Santa Clara, CA, USA

ABSTRACT

Physical Vapor Deposition (PVD) systems are among the most widely used systems in fabs. To extend PVD technology, a highly successful platform has been redesigned to meet sub-90nm requirements. Over 14 years of being used in production (which continues till today), vast modifications were made to both the PVD mainframe unit and its chambers to keep abreast of ever changing design nodes and device designs. 

David J. Hilton, Busch Semiconductor Vacuum Group, Morgan Hill, CA, USA

ABSTRACT

In times past, semiconductor vacuum processing was typically done with "oilsealed" wet rotary vane, or rotary piston-type vacuum pumps. Variations of the actual operation of these types of pumps were not so great that substitution from one manufacturer to the next was not difficult. With today's modern dry vacuum pumps, this is no longer the case. Over the past decade or so, there have been several different types of these dry vacuum pumps, designed and manufactured, which have very striking differences in mechanical design. 

Gerhard Schiroky & Gary Henrich, Swagelok Company, Solon, Ohio, USA

ABSTRACT

A study was performed to determine the corrosion behavior of welded tube samples of ultralow-manganese and low-manganese 316L alloys in corrosive gaseous environments. First, a weld-fume analysis was performed to determine which elements evaporate to a significant extent during orbital welding with 316L test samples containing different amounts of manganese. Second, welded tube sections were exposed to corrosive gases and the surfaces were characterized by scanning electron microscopy (SEM) both in the short term (24 h) and in the long term (28 days). It has been claimed that during welding, the manganese evaporates from the weld pool and redeposits in the heat-affected zone, primarily downstream of the weld pool, causing corrosion to occur. 

Giuseppe Fazio & Massimo Strada, ST Microelectronics, Central R&D, Agrate Brianza, Italy

ABSTRACT

In the modern fab process control is very important. The process control may be improved by modifications to equipment. The wafer-cleaning process is one of the most important and critical steps in semiconductor manufacturing. In this process two or more chemicals are mixed and it is very important to have the correct concentrations. Repeatability and reproducibility in concentration impact on the process quality. The chemical input usually is guaranteed by mechanical flow controllers installed in every chemical line, where a narrowing regulated by a valve provides the correct flows entering the DIW line. The performance of such flow controllers is affected by several variables: chemical pressure or DIW flow, which could generate fluctuations during the chemical injection phase.

Mark Osborne, Editor-in-Chief, Semiconductor Fabtech

ABSTRACT

Atomic Layer Deposition (ALD) has long been hailed as a next generation technology, enabling semiconductors to enter the nanoworld that promises to keep pace with the demands of Moore's Law. Only in the last two years has this technology moved from the lab into the fab. The pace of adoption is expected to increase significantly at the 70nm node for DRAM and the 65-45nm nodes for logic. ALD is a variant of chemical vapor deposition (CVD) and therefore requires reactor and reactor-related components for operation under controlled vacuum conditions. 

Dave Wehrs & Chuck Gould, NT International & Huaping Wang, Entegris, Inc.

ABSTRACT

The accurate control of liquid flow is critical for attaining high process yields in wet etch, CMP delivery, and on-demand chemical blending applications. To maintain high purity, a flow control technology must minimize particle addition to the fluid stream. This article will present laboratory data to demonstrate the low levels of particle generation associated with the use of a differential pressure (DP)-based flow controller. The flow controller performs closed-loop control using direct flow and pressure measurement, and is used for in-situ monitoring and control of a process liquid flow rate. Differential pressure flow measurement technology allows this device to measure liquid flow rate without the use of moving parts. The flow controller’s valve technology provides control with low particle addition to the fluid stream during actuation. The valve seat and diaphragm are designed to minimize dead volume and fluid shear, reducing the possibility of process contamination. Also, to avoid excessive movement, the valve diaphragm actuation stroke is minimized. Testing was completed under three different conditions that represent probable-use cases of the device. Test results indicate low levels of particle generation during flushing and normal operation of the device confirming that semiconductor equipment users can use the flow controller for high-purity applications sensitive to particle generation. This provides users with another tool
for managing materials integrity.

Michael Bonner & Randall Clark, IBM Microelectronics

ABSTRACT

Implementing an active RF sesorbased endpoint of PECVD chamber cleaning on several process tools in a wafer fab production line has demonstrated how this approach can reduce gas consumption and processing times, as well as increase tool throughput and improve onwafer particle performance. 

F. Somboli & G. Fazio, ST Microelectronics

ABSTRACT

The pressure rate of rise is a standard method to test for leaks in vacuum systems, and to control/calibrate MFCs (mass flow controller). Unfortunately, the calibration of ROR sensors is often neglected. In this way, there is the risk to perform controls using equipment that could be worse than the tested system.  In this paper we describe a method and a simple device to calibrate, quickly and accurately, the pressure ROR system. The suggested device can help engineers to avoid the above-described problem.