System and method for depth-selectable x-ray analysis

An x-ray source comprising:

• at least one electron source configured to generate at least one electron beam having an electron energy in a range of 5 keV to 30 keV;
• and
• at least one target comprising:
• at least one thermally conductive substrate;
• and
• a plurality of sub-sources on or embedded in at least a portion of the at least one thermally conductive substrate, the sub-sources separate from one another and in thermal communication with the at least one thermally conductive substrate, at least one sub-source of the plurality of the sub-sources comprising silicon carbide and configured to emit Si x-ray emission line x-rays in response to bombardment by the at least one electron beam.

A method of x-ray analysis, the method comprising:

• bombarding a target material comprising silicon carbide with electrons with kinetic energy in a range of 5 keV to 30 keV;
• emitting Si x-ray emission line x-rays from the target material;
• irradiating a sample with at least some of the Si x-ray emission line x-rays;
• and
• detecting x-rays and/or electrons emitted from the sample.

An x-ray illumination system comprising:

• at least one x-ray source comprising at least a first x-ray sub-source and a second x-ray sub-source, the first and second x-ray sub-sources on or embedded in at least one thermally conductive substrate, the first x-ray sub-source comprising a first material configured to generate first x-rays in response to electron bombardment of the first x-ray sub-source, the second x-ray sub-source comprising a second material different from the first material, the second material configured to generate second x-rays in response to electron bombardment of the second x-ray sub-source;
• and
• a plurality of x-ray optical trains comprising:
• a first optical train comprising at least one first collimating x-ray mirror, at least one first energy-selective x-ray monochromator or multilayer, and at least one first focusing x-ray mirror, the first optical train configured to be positioned to direct at least some of the first x-rays emitted from the first x-ray sub-source to irradiate a sample;
• and
• a second optical train comprising at least one second collimating x-ray mirror, at least one second energy-selective x-ray monochromator or multilayer, and at least one second focusing x-ray mirror, the second optical train configured to be positioned to direct at least some of the second x-rays emitted from the second x-ray sub-source to irradiate the sample.

An x-ray photoelectron spectroscopy system comprising:

• at least one x-ray source comprising a plurality of x-ray sub-sources on or embedded in at least one thermally conductive substrate, the x-ray sub-sources comprising a plurality of materials configured to generate x-rays in response to electron bombardment;
• a plurality of x-ray optical trains, each optical train comprising at least one collimating x-ray optical element, at least one energy-selective optical element, and at least one focusing x-ray optical element, the plurality of x-ray optical trains configured to be positioned to direct at least some of the x-rays emitted from a selected one of the plurality of x-ray sub-sources to irradiate a sample;
• a sample chamber configured to contain the sample at a sample pressure;
• a first chamber and a first electrostatic lens contained in the first chamber at a first pressure less than the sample pressure, the sample chamber and the first chamber separated from one another by a first wall having a first aperture configured to allow at least some photoelectrons from the sample to propagate from the sample chamber to the first chamber;
• and
• a second chamber and a second electrostatic lens contained in the second chamber at a second pressure less than the first pressure, the first chamber and the second chamber separated from one another by a second wall having a second aperture configured to allow at least some of the photoelectrons in the first chamber to propagate to the second chamber.