Lanthanum Hexaboride is the optimum cathode material for use in SEM, TEM, X-Ray Microanalysis, and Electron Beam Lithography.
- Low potential barrier (work function)
- High melting point and stability at high temperatures
- Low vapor pressure-reduces evaporation lost
- Chemical stability
LaB6 beam is ten times brighter than tungsten, has superior resolution-wide range of acceleration voltages. It provides sharp and clear pictures even to the smallest details. The initial brightness of a Denka Model 3 cathode (1×106 A/cm2.Str) is substantially better than that of competing mini-vogel type cathodes (typically 5×105 A/cm2.Str).
Standard (Round) Tips are provided with a 90° cone and 15 µm radius round tip. Flat (Truncated) Tips are recommended for applications where stability and long lifetime are the prime considerations, and where some degree of brightness can be sacrificed. Flat tips are available in eight configurations. Sharp tips are recommended for applications where initial brightness is the foremost consideration and where shorter lifetime can be accepted. Sharp tips are available in two configurations. All standard Denka M-3 LaB6 Cathodes are provided with a 90° cone angle and a 15 µm radius round tip. These are just the standard Denka LaB6 Cathodes that are in stock. The complete line of Denka Lab6 filaments is available through Electron Microscopy Sciences.
Heat and vacuum are the final determinants of any cathode tip's life, but at 1550 °C and a vacuum of 10 - 7 Torr, a service life of about 500 hours can be achieved.
Every Denka Model 3 cathode offers a stability of better than 3% per hour at 1550 °C and Denka Model3 LaB6 cathodes are designed as direct replacement for tungsten filaments
