Kla Tencor Corporation

Xiaoxu Lu

Yung-Ho Alex Chuang

John Fielden

Justin Dianhuan Liou

J Joseph Armstrong

Vladimir L Dribinski

Yujun Deng

Baigang Zhang

Ivan Maleev

Justin Dianhuan Loiu

An inspection system/method in which first optics direct continuous wave (CW) light at 181-185 nm to an inspected article, and second optics redirect image information affected by the article to detectors. A laser assembly generates the CW light by generating fourth harmonic light from first fundamental CW light having a first wavelength between 1 and 1.1 &#x3bc;m, generating fifth harmonic light by mixing the fourth harmonic light with the first fundamental CW light, and mixing the fifth harmonic light with second light having a second wavelength between 1.26 and 1.82 &#x3bc;m. An external cavity mixes the first light and the fourth harmonic light using a first nonlinear crystal. The CW light is generated using a second cavity that passes circulated second fundamental or signal CW light through a second nonlinear crystal, and directing the fifth harmonic light through the second nonlinear crystal.

183 nm CW laser and inspection system

A laser assembly generates continuous wave (CW) laser output light in the range of approximately 181 nm to approximately 185 nm by generating fourth harmonic light from first fundamental CW light having a first fundamental wavelength between 1 &#x3bc;m and 1.1 &#x3bc;m, generating fifth harmonic light by mixing the fourth harmonic light with the first fundamental CW light, and then mixing the fifth harmonic light with second fundamental or signal CW light having a second wavelength between 1.26 &#x3bc;m and 1.82 &#x3bc;m. The fifth harmonic light is generated using an external cavity that circulates first fundamental CW light through a first nonlinear crystal, and by directing the fourth harmonic light through the first nonlinear crystal. The laser output light is generated using a second cavity that passes circulated second fundamental or signal CW light through a second nonlinear crystal, and directing the fifth harmonic light through the second nonlinear crystal.

A deep ultra-violet (DUV) continuous wave (CW) laser includes a fundamental CW laser configured to generate a fundamental frequency with a corresponding wavelength between about 1 &#x3bc;m and 1.1 &#x3bc;m, a third harmonic generator module including one or more non-linear optical (NLO) crystals that generate a third harmonic and an optional second harmonic, and a fifth harmonic generator. The fifth harmonic generator module includes a cavity resonant at the fundamental frequency, and combines the fundamental frequency with the third harmonic in a first NLO crystal to generate a fourth harmonic, then combines the fourth harmonic with unconsumed fundamental frequency in a second NLO crystal to generate the fifth harmonic. One or more lenses are used to focus the third and fourth harmonics in the first and second NLO crystals, respectively.

CW DUV laser with improved stability

A repetition rate (pulse) multiplier includes one or more beam splitters and prisms forming one or more ring cavities with different optical path lengths that delay parts of the energy of each pulse. A series of input laser pulses circulate in the ring cavities and part of the energy of each pulse leaves the system after traversing the shorter cavity path, while another part of the energy leaves the system after traversing the longer cavity path, and/or a combination of both cavity paths. By proper choice of the ring cavity optical path length, the repetition rate of an output series of laser pulses can be made to be a multiple of the input repetition rate. The relative energies of the output pulses can be controlled by choosing the transmission and reflection coefficients of the beam splitters. Some embodiments generate a time-averaged output beam profile that is substantially flat in one dimension.

Laser repetition rate multiplier and flat-top beam profile generators using mirrors and/or prisms

A high brightness laser-sustained broadband light source includes a gas containment structure and a pump laser configured to generate a pump beam including illumination of a wavelength at least proximate to a weak absorption line of a neutral gas contained in the gas containment structure. The broadband light source includes one or more anamorphic illumination optics configured to focus the pump beam into an approximately elliptical beam waist positioned in or proximate to the center of the gas containment structure. The broadband light source includes one or more first collection optics configured to collect broadband radiation emitted by the plasma in a direction substantially aligned with a longer axis of the elliptical beam waist.

High brightness laser-sustained plasma broadband source

The broadband light source includes a gas containment structure and a pump laser for generating a pump beam including illumination of a wavelength near that of a weak absorption line of a neutral gas contained in the gas containment structure. The broadband light source also includes anamorphic optics for focusing the pump beam into an elliptical beam waist positioned in or near the center of the gas containment structure. The broadband light source also includes collection optics for collecting broadband radiation emitted by the plasma in a direction aligned with a longer axis of the elliptical beam waist.

A deep ultra-violet (DUV) continuous wave (CW) laser includes a fundamental CW laser configured to generate a fundamental frequency with a corresponding wavelength between about 1 &#x3bc;m and 1.1 &#x3bc;m, a third harmonic generator module including one or more periodically poled non-linear optical (NLO) crystals that generate a third harmonic and an optional second harmonic, and one of a fourth harmonic generator module and a fifth harmonic generator. The fourth harmonic generator module includes a cavity resonant at the fundamental frequency configured to combine the fundamental frequency with the third harmonic to generate a fourth harmonic. The fourth harmonic generator module includes either a cavity resonant at the fundamental frequency for combining the fundamental frequency with the third harmonic to generate a fifth harmonic, or a cavity resonant at the second harmonic frequency for combining the second harmonic and the third harmonic to generate the fifth harmonic.

Methods and systems for minimizing interference among multiple illumination beams generated from a non-uniform illumination source to provide an effectively uniform illumination profile over the field of view of an inspection system are presented. In some examples, a pulsed beam of light is split into multiple illumination beams such that each of the beams are temporally separated at the surface of the specimen under inspection. In some examples, multiple illumination beams generated from a non-uniform illumination source are projected onto spatially separated areas on the surface of the specimen. A point object of interest illuminated by each area is imaged onto the surface of a time-delay integration (TDI) detector. The images are integrated such that the relative position of the illumination areas along the direction of motion of the point object of interest has no impact on the illumination efficiency distribution over the field of view.

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San Jose, CA, United States of America

Xiaoxu Lu