Herve A. Besaucele

Performance Demonstration of Significant Availability Improvement in Lithography Light Sources using GLX Control System

Increasing productivity demands on leading-edge scanners require greatly improved light source availability. This translates directly to minimizing downtime and maximizing productive time, as defined in the SEMI E10 standard. Focused efforts to achieve these goals are ongoing and Cymer has demonstrated significant improvements on production light sources. This paper describes significant availability improvements of Cymer light sources enabled by a new advanced gas management scheme called Gas Lifetime eXtensioTM (GLTM) control system. Using GLX, we have demonstrated the capability of extending the pulse-based interval between full gas replenishments to 1 billion pulses on our XLA light sources, as well as significant extension in the time-based interval between refills. This represents a factor of 10X increase in the maximum interval between full gas replenishments, which equates to potential gain of up to 2% in productive time over a year for systems operating at high utilization. In this paper, we provide performance data on extended (1 billion pulse) laser operation without full gas replenishment under multiple actual practical production environments demonstrating the ability to achieve long gas lives with very stable optical performance from the laser system. In particular, we have demonstrated that GLX can provide excellent stability in key optical performance parameters, such as bandwidth, over extended gas lives. Further, these stability benefits can be realized under both high and low pulse accumulation scenarios. In addition, we briefly discuss the potential for future gas management enhancements that will provide even longer term system performance stability and corresponding reductions in tool downtime.

Dual-chamber ultra line-narrowed excimer light source for 193 nm lithography

Since the announcement in March 2002 of plans to develop an advanced light source to meet the future spectral power and cost requirements of photolithography, we have made significant progress in the development and productization of the core technology for an ultra line-narrowed, excimer light source based on a master oscillator-power amplifier (MOPA) approach. In this paper, we will focus on the architecture and performance of the first generation of production-ready, MOPA-based ArF light sources developed at Cymer, Inc. This first generation of MOPA-based ArF light sources is referred to as the XLA 100 product series.

Long-term reliable operation of a MOPA-based ArF light source for microlithography

Since the introduction of the XLA-100 in January 2003, we have built, tested, and shipped a large number of XLA-100 MOPA lasers to microlithography scanner manufacturers. Some systems have already been installed at chip fabrication lines. To ensure product design robustness, we have been performing a long-term system performance test of an XLA-100 laser at Cymer. In this paper, we will report optical performance of the XLA-100 we see during manufacturing final tests, and a summary of the long term testing.

Performance of very high repetition rate ArF lasers

We report the performance of a very high repetition rate ArF laser optimized for next generation, high NA, high throughput scanner. The lasers repetition rate exceeds 4kHz, at 5mJ, and at bandwidths of less than 1.2 pm. We discuss the complexity of high power operation, and make some estimates about the robustness of this technology. In particular, we discuss the risks of scaling to this high repetition rate, and prospects of exceeding 4kHz to near 6kHz with 95 percent bandwidths of less than 1pm.

Comparison of ArF and KrF laser performance at 2 kHz for microlithography

Exposure tools for 193nm lithography are expected to use Argon-Fluoride lasers at repetition rates of at least 2kHz. We are showing that, by revisiting several key technologies, the performance and reliability of ArF lasers at 2 kHz are trending towards a level comparable to KrF lasers.

Performance characteristics of ultranarrow ArF laser for DUV lithography

Today, commercial line-narrowed ArF lasers for Deep-UV lithography are typically producing spectral bandwidth of 0.6 pm FWHM. This value forces the stepper/scanner manufacturers to use large amount of CaF2 in the lens design as well as fused silica in order to compensate for chromatic aberrations. We describe in this paper the parameters - such as pulse duration, fluorine concentration and divergence - which influence the line-narrowing efficiency of ArF laser. We are also presenting result obtained using a new optical cavity design using an etalon as output coupler that provides bandwidth of 0.3 pm at FWHM and 0.8 pm for 95 percent of the energy, performance that could allow to greatly reduce the need for CaF2.