摘要:
The invention is directed to a method and arrangements for the suppression of debris in short-wavelength radiation sources based on a plasma, particularly for EUV sources for semiconductor lithography. The object of the invention is to find a novel possibility for suppressing the particle flow (debris) from a plasma which keeps the debris away from primarily optical components located downstream without excessive attenuation of the desired radiation emitted from the plasma. According to the invention, this object is met in that a buffer gas is injected inside the filter structure of the debris filter lateral to openings that are provided for passing the radiation. The filter structure generates a flow resistance in direction of the plasma and in direction of propagation of the radiation so that an increased gas pressure of buffer gas remains limited to a defined volume layer in the debris filter relative to the pressure in the vacuum chamber, and the buffer gas exiting from the filter structure of the debris filter is sucked out of the vacuum chamber by vacuum pumps.
摘要:
The invention is directed to an arrangement for the suppression of unwanted spectral components (‘out-of-band’ radiation, as it is called) in a plasma-based radiation source. The object of the invention is to find a novel possibility for the suppression of unwanted spectral components in radiation exiting from a plasma-based EUV radiation source which permits a simple suppression of out-of-band radiation outside the desired EUV range without requiring costly manufacturing and adjustment of diffraction gratings. This object is met according to the invention in that a filter unit is provided between the plasma and an application location of the EUV radiation, which filter unit has at least one gas curtain comprising at least one rapidly flowing gas whose molecules have no absorption maxima for the desired EUV radiation and intensive absorption maxima for other, unwanted wavelengths that are emitted, at least in the IR region. For the purpose of generating the gas curtain, at least one slit nozzle and an efficient gas sink are arranged laterally opposite one another with respect to an optical axis of the beam bundle in order to limit the gas curtain in a spatially defined manner and to remove it again from the vacuum chambers as completely as possible.
摘要:
The invention is directed to a method and arrangements for the suppression of debris in short-wavelength radiation sources based on a plasma, particularly for EUV sources for semiconductor lithography. The object of the invention is to find a novel possibility for suppressing the particle flow (debris) from a plasma which keeps the debris away from primarily optical components located downstream without excessive attenuation of the desired radiation emitted from the plasma. According to the invention, this object is met in that a buffer gas is injected inside the filter structure of the debris filter lateral to openings that are provided for passing the radiation. The filter structure generates a flow resistance in direction of the plasma and in direction of propagation of the radiation so that an increased gas pressure of buffer gas remains limited to a defined volume layer in the debris filter relative to the pressure in the vacuum chamber, and the buffer gas exiting from the filter structure of the debris filter is sucked out of the vacuum chamber by vacuum pumps.
摘要:
The invention is directed to an arrangement for the suppression of unwanted spectral components (‘out-of-band’ radiation, as it is called) in a plasma-based radiation source. The object of the invention is to find a novel possibility for the suppression of unwanted spectral components in radiation exiting from a plasma-based EUV radiation source which permits a simple suppression of out-of-band radiation outside the desired EUV range without requiring costly manufacturing and adjustment of diffraction gratings. This object is met according to the invention in that a filter unit is provided between the plasma and an application location of the EUV radiation, which filter unit has at least one gas curtain comprising at least one rapidly flowing gas whose molecules have no absorption maxima for the desired EUV radiation and intensive absorption maxima for other, unwanted wavelengths that are emitted, at least in the IR region. For the purpose of generating the gas curtain, at least one slit nozzle and an efficient gas sink are arranged laterally opposite one another with respect to an optical axis of the beam bundle in order to limit the gas curtain in a spatially defined manner and to remove it again from the vacuum chambers as completely as possible.
摘要:
The invention is directed to an arrangement for debris reduction in a radiation source based on a plasma, particularly for generating bundled radiation in the extreme ultraviolet (EUV) spectral region. The object of the invention, to find a novel possibility for beam shaping and debris reduction in a radiation source based on a plasma which substantially increases the life of collector optics without having to tolerate a substantial reduction in transparency or a sudden destruction of the protective mechanism, is met according to the invention in that exchangeable additional optics are arranged in the radiation path between a conventional debris filter and the collector optics, wherein a distance-increasing intermediate imaging of the source location relative to the collector optics is provided by the additional optics for further debris reduction.
摘要:
The invention is directed to a method and an arrangement for stabilizing the average emitted radiation output of a pulsed radiation source. It is the object of the invention to find a novel possibility for stabilizing the average emitted radiation output of a pulsed radiation source which enables a reliable regulation even when there is no sufficiently reliable manipulated variable for influencing the emitted pulse energy (Ei). According to the invention, this object is met in that the individual pulse energy (Ei) of the current radiation pulse is measured, the deviation of the current individual pulse energy (Ei) from a previously determined target value (E0) is determined, and the pulse interval (Δti+1) preceding the triggering of the next radiation pulse is controlled depending on the magnitude of the deviation between the current individual pulse energy (Ei) and the target value (E0) of the pulse energy.
摘要翻译:本发明涉及用于稳定脉冲辐射源的平均发射辐射输出的方法和装置。 本发明的目的是找到一种用于稳定脉冲辐射源的平均发射辐射输出的新颖可能性,即使当没有足够可靠的操纵变量来影响发射的脉冲能量(Ei)时,也能够进行可靠的调节。 根据本发明,满足目的在于测量当前辐射脉冲的单个脉冲能量(Ei)的目的,确定当前独立脉冲能量(Ei)与先前确定的目标值(E0)的偏差,以及 根据当前个体脉冲能量(Ei)与脉冲能量的目标值(E0)之间的偏差大小来控制触发下一个辐射脉冲之前的脉冲间隔(&Dgr; ti + 1)。
摘要:
The invention is directed to a method and an arrangement for stabilizing the average emitted radiation output of a pulsed radiation source. It is the object of the invention to find a novel possibility for stabilizing the average emitted radiation output of a pulsed radiation source which enables a reliable regulation even when there is no sufficiently reliable manipulated variable for influencing the emitted pulse energy (Ei). According to the invention, this object is met in that the individual pulse energy (Ei) of the current radiation pulse is measured, the deviation of the current individual pulse energy (Ei) from a previously determined target value (E0) is determined, and the pulse interval (Δti+1) preceding the triggering of the next radiation pulse is controlled depending on the magnitude of the deviation between the current individual pulse energy (Ei) and the target value (E0) of the pulse energy.
摘要:
The invention is related to the adjustment of characteristics of a beam bundle of high-energy radiation emitted from a plasma, particularly for applications in semiconductor lithography. For acquiring and adjusting characteristics of a beam bundle of high-energy radiation emitted from a plasma and focused by means of collector optics, an intensity distribution of the radiation is acquired over the cross section of a convergent beam bundle in a measuring plane perpendicular to the optical axis in front of an intermediate focus of the collector optics, and intensity values are recorded in defined sectors for a quantity of reception regions of a measuring device which are aligned with different radii concentric to the optical axis, and measured quantities and control variables are determined from a comparison of the intensity values of different sectors for aligning the collector optics.
摘要:
The present invention is directed to an arrangement for switching high electric currents by way of a gas discharge at high voltages or for generating gas discharge plasma emitting EUV radiation. It is the object of the invention to find a novel possibility for generating a hollow cathode plasma that permits a longer life of the cathodes of short wavelength-emitting gas discharge radiation sources and pseudospark switches, also in high-power operation. This object is met in that the metal wall between the hollow cathode space and the discharge space has a thickness on the order of the centimeter range so that the openings of the metal wall change into relatively long channels and in that substantially radially extending cooling channels are introduced in the metal wall to reduce the ion erosion of the metal wall of the hollow cathode through efficient cooling.
摘要:
The object of an arrangement and a method for the generation of extreme ultraviolet radiation is to construct the radiation source with an increased lifetime of the electrodes for using various emitters, wherein deposits inside the discharge chamber are reduced considerably when using metal emitters. The starting material is supplied as a continuous series of individual volumes which are introduced successively by directed injection and are pre-ionized by a pulsed energy beam. At least the electrode that is thermally loaded to a comparatively greater degree is constructed as a rotating electrode.