Course #88

Plasma Etching for CMOS Technology and ULSI Applications

October 20-22, 2010. Dresden, Germany

INSTRUCTOR
Dr.  Olivier Joubert, LTM/CNRS, Grenoble, France

TECHNOLOGY FOCUS 
Extensive efforts to miniaturize semiconductor devices is largely attributed to lithography and etching technologies that allow semiconductor thin films patterning in the range of dimensions determined by the semiconductor road map. During more than 30 years, classical materials, such as aluminum, SiO2, and poly-silicon, have been integrated in semiconductor devices. 

Nowadays, the technology imposes to work with new materials at each technological node. The integration of new high k and low k dielectric materials, metals at the front and back end of device fabrication, bring on new problem categories. This imposes the necessity to quickly build up expertise at a rate unprecedented in all the history of semiconductor manufacturing. 

COURSE CONTENT AND OBJECTIVES 
This course is intended to provide an understanding of plasma processes for CMOS applications and ULSI technology. We will discuss fundamental and practical aspects of front end and back end plasma processes for deep submicron CMOS logic processes. 
The course is based on experimental results obtained using commercial etchers connected to very powerful diagnostics of the plasma and the plasma surface interaction. The discussions cover several aspects of etch processes of materials integrated in advanced CMOS devices, etch mechanisms, and situations that may be encountered for some important plasma processes. 

Fundamental parameters obtained from advanced characterizations are used to discuss and analyze plasma etch processes. The emphasis is on real problems, fundamental understanding of processes used in manufacturing, considerations for integration with other steps, and issues brought by the fast device scaling. 
Processes covered in detail include silicon gate patterning and all the problems related to critical dimension control as well as preliminary results on high k dielectric etching. The etch processes associated with the integration of low k materials will be extensively discussed. 

Wednesday 

Fundamentals in Plasma Processing 

• Ion Neutral/Synergy
• Impact of Neutral Flux to Ion Flux Ratio on Plasma Processes 
• Etch Anisotropy
• Passivation Layer Formation in Plasma Processes
• Temperature Effects in Plasma Etching
• Microscopic Uniformity in Plasma Etching
• Impact of Aspect Ratio on Etching Processes
• Charging Effects in Plasma Etching
• Impact of Reactor Wall on Plasma Processing
• Micro-Trenching Formation 
• Etch Mechanism of Silicon in Halogen Based Plasmas
• SiO₂ Etch Mechanisms
• Polymer Etching for Microelectronics Applications

Thursday

Silicon, Metal and High K Etching Processes for CMOS Applications 

• Thin Gate Oxide Behaviour during Gate Etch Processes
• Silicon Recess during Gate Etch Processes
• Impact of Plasma Processes on 193 Nm Resists
• Hard Mask Opening Processes
• Silicon Gate Etching in Inductively Coupled Plasmas: Hbr/Cl₂/O₂, Hbr/Cl₂/O₂/CF₄, SF₆/CH₂F₂ Chemistries
• Metal Gate Etching
• The Etch Challenges of High K Materials
• Chamber Wall Coating during Si/Metal/High K Etching
• Chamber Wall Cleaning Strategies for CMOS Applications

Oxide and Low k Etching 

• Fundamentals in SiO₂ Etching 
• Low k Materials in Advanced Interconnects 

Friday 

Oxide and Low k Etching (Cont'd) 

• Mechanisms of Low k Polymer Etching in Medium Density and High Density Plasmas 
• Etch Mechanisms of SiOC-based Materials 
• Selectivity Issues 
• Fluorocarbon Film Thickness Measurement by XPS 
• The Impact of Porosity on Etching Mechanisms of SiOC-based Materials 
• Dual Hard Mask Strategies 
• Impact of Ashing Plasmas and Chemistries on Low k Material Modifications 

(See also course #87, October 18-19, 2010 )

Regular Course Fee: EUR 1915
Courses #87 + #88 = 5 days: EUR 2995

Early Registration Course Fee: EUR 1720
Courses #87 + #88 = 5 days: EUR 2725
This applies to firm registrations received 2 months before course start. 

University Student and Faculty Rate: Two university participants are welcome to attend for one course fee if payment is to be made from university funds.

Deliverables: The course fee covers tuition, course material, and the day conference packages (morning/afternoon refreshments, lunches etc) paid on your behalf to the course venue. Accommodation is not included.