The QUALI-LINE® QUANTÅ: A Chemical Monitoring System for Cobalt Interconnects

The use of tungsten as a transistor contact metal at advanced nodes is a barrier to performance because of gapfill and resistance. Thanks to its ability to fill small features with a considerably thinner barrier, cobalt (Co) provides intrinsically excellent resistance at small dimensions.

ECI Technology’s fully automated QUALI-LINE^® QUANTÅ online chemical metrology for Co interconnects metallization processes includes CVS electrochemical technology in combination with Potentiometric and Spectroscopic Titration methods to find the concentrations of both inorganic and organic components with the maximum degree of precision and accuracy.

The total analysis time of QUALI-LINE QUANTÅ is less than 22 minutes based on the chemistry, with a standard accuracy and RSD specification of Co and Boric Acid of 2% and 2%, respectively.

The system can ensure pH accuracy and RSD of 0.01 values and offer a <0.01 pH with a narrower process window. Standard conductivity accuracy and RSD are 3% and 2%, respectively. For organic additive, the typical specification of accuracy and RSD is 3.5% and 2%.

Key Features

An Analyzer Health Monitor notifies the need for maintenance when required

An Automatic Standard Generator ensures a repeatable and accurate standard for precise calibration and validation, substituting a costly pre-mixed standard

The system is monitored by in-built leak detectors that trigger an emergency shutdown process when there is a leak

A Bath Health Monitor is a dedicated module specifically engineered for the analyses of contaminants, breakdown productsand bath aging

The system uses ECI’s wide-scale library of Co ChemPacks applications

Up to four plating tanks can be monitored by the system

Key Benefits

Supports conventional, highand low Co concentration chemistries for high-volume manufacturing and R&D; users can systems can easily convert the system to analyze various Co chemistries

Enhanced for state-of-the-art via filling and trench structures

Can be combined easily with the most advanced plating tools

Complies with stringent tolerance specifications for successful deposition of each layer

Precision-crafted, low maintenance components

For more than 25 years, QUALI-LINE^® Chemical monitoring systems have been at the forefront of the industry when it comes to the analysis and control of Copper Damascene processes. The QUALI-LINE analyzers for cobalt are now in their second generation and include extended capabilities. Since the inception of the system in 2015, ECI has sold more than 50 units.

Configured to Meet Users’ Needs

The cabinet is made of FM4910-compliant materials. Four main sections are provided in the system for isolating chemical handling sections from electronics.

Image Credit: ECI Technology

Technical Specifications

NOWPak^® reagent delivery system has been provided

Dimensions—762 mm (30″) W x 2061 mm (81.1″) H x 610 mm (24″) D

Exhaust—4″ OD chemical exhaust

AC—180 to 245 VAC, 50/60 Hz, 15 A

Compliance to standards—CE, SEMI F-47, SEMI S2-S8, NFPA-79

Data communication—Multiple communication protocols: Ethernet/RJ45 port supporting SECS/GEM, RS-232and TCP/IP with the fab’s host