Method and apparatus for surface diagnostics

A method of analyzing a surface including unknown species of matter comprising the steps of:

• directing a probe beam at the surface to cause a sample of material to be removed therefrom;
• directing a non-resonant ionizing beam of radiation at the removed sample proximate the surface, said ionizing beam having an intensity sufficient to induce non-resonant multi-photon ionization of said sample, whereby species of matter included in said sample will be non-selectively ionized;
• and
• subjecting the ionized sample to mass-spectrometric analysis to determine the nature of said species.

A method of analyzing a surface with comparatively little damage thereto wherein a probe beam is directed at said surface to cause a sample of material to be removed therefrom for subsequent analysis, said method comprising the steps of:

• adjusting the intensity of said probe beam so as to remove only minute amounts of material from said surface, whereby minimal damage is done to said surface;
• directing a non-resonant ionizing beam of radiation at the removed sample in a spatial region proximate said surface, said ionizing beam having an intensity sufficient to induce non-resonant photoionization of said sample, whereby species of matter in said sample will be non-selectively ionized;
• and
• subjecting the ionized sample to mass spectral analysis to determine the nature of said unknown species.

Apparatus for use in analyzing a surface including unknown species of matter comprising:

• probe beam means providing a probe beam directed at the surface under examination to cause a sample of material to be removed therefrom;
• ionizing beam means providing a non-resonant ionizing beam of radiation directed at a spatial region proximate said surface, and having an intensity sufficient to induce non-resonant photoionization of said sample in said spatial region, whereby species of matter included in said sample will be non-selectively ionized;
• and
• a mass spectrometer disposed with respect to said spatial region for analyzing the ionized sample.

Apparatus for use in analyzing a surface of a specimen including unknown species of matter comprising:

• an evacuation chamber;
• mounting means disposed within said chamber for holding said specimen;
• probe beam means providing a probe beam directed at a surface of said specimen to cause a sample of material to be removed therefrom;
• ionizing beam means providing a non-resonant ionizing beam of radiation directed at a spatial region proximate said surface, said ionizing beam having an intensity sufficient to induce non-resonant photoionization of said sample in said spatial region, whereby species of matter included in said sample will be non-selectively ionized;
• wherein said evacuation chamber includes a field-free ion drift region;
• acceleration means disposed within said evacuation chamber for propelling the ionized sample across said drift region;
• and
• detector means disposed within said chamber for detecting the ionized sample exiting from said drift region, said above-named means being operatively connected for conducting time-of-flight mass spectral analysis of the ionized sample.

Apparatus for use in analyzing a surface including unknown species of matter comprising:

• probe beam means providing a probe beam directed at the surface under examination to cause a sample of matreial to be removed therefrom;
• ionizing beam means providing non-resonant ionizin beam of radiation directed at a spatial region proximate said surface, and having an intensity sufficient to induce non-resonant multiphoton ionization of said sample in said spatial region, whereby species of matter included in said sample will be non-selectively ionized;
• and
• a mass spectrometer disposed with respect to said spatial region for analyzing the ionized sample.

Apparatus for use in analyzing a surface of a specimen including unknown species of matter comprising:

• an evacuation chamber;
• mounting means disposed within said chamber for holding said specimen;
• probe beam means providing a probe beam directed at a surface of said specimen to cause a sample of material to be removed therefrom;
• ionizing beam means providing a non-resonant ionizing beam of radiation directed at a spatial region proximate said surface, said ionizing beam having an intensity sufficient to induce non-resonant multiphoton ionization of said sample in said spatial region, whereby species of matter included in said sample will be nonselectively ionized;
• wherein said evacuation chamber includes a field-free ion drift region;
• acceleration means disposed within said evacuation chamber for propelling the ionized sample across said drift region;
• ion reflector means disposed in operative association with said ion drift region so as to reflect said ionized sample toward said detector means;
• and
• detector means disposed within said chamber for detecting the ionized sample exiting from said drift region, said above-named means being operatively connected for conducting time-of-flight mass spectral analysis of the ionized sample.

A method of analyzing a surface including unknown species of matter comprising the steps of:

• directing a probe beam at the surface to cause a sample of material to be removed therefrom;
• directing a non-resonant ionizing beam of radiation at the removed sample in an ionizing region proximate the surface, said ionizing beam having an intensity sufficient to induce saturated non-resonant multi-photon ionization of said sample in said ionizing region, whereby species of matter included in said sample will be non-selectively ionized;
• and
• subjecting the ionized sample to mass spectrometric analysis to determine the nature of said species.