JOMESA is manufacturer of SEM Filter mounts and SEM particle traps. Both products contain two markers, visible in optical analysis (HFD) as well as in SEM (PSE)
By determining the markers in both systems (HFD and PSE), particle coordinates can be calculated relative to the marker positions.

JOMESA SEM Filter mounts fixation of particles on filters by JOMESA fixation solution

JOMESA SEM Particle traps can be optionally equipped with an unique barcode.

Investigation of filters without fixation solution is possible only in low vacuum condition. However the risk of loosing particles by charging effects is usually not acceptable. Even in low vacuum fixation is recommended.
Analysis of filters in high vacuum needs JOMESA conductivity solution. This organic ionic liquid contains only the elements C, O, N and H.

Analysis of particle traps is possible only in low vacuum.

Specific designed filter/trap holdes allow direct SEM-EDX analysis:
Filter shuttle for Single Stage PSE:

4 Stage PSE