Tungsten filaments

Manufactured by Energy Beam Sciences (EBS) using the most recent advances in ceramic and metallurgical technologies these high quality, high stability EM filaments exceed the specifications of the original microscope manufacturers. Available for all major microscope brands.

Advantages of EBS EM tungsten filaments are:

Minimum tip radius for a coherent beam
Rigid attachment of filament wire to posts for increased stability
Fully stress relieved for enhanced lifetime
Polished post ends for better contact
Precise dimensions for minimal alignment adjustments
Better long term economy

Filament bases are made using high quality ceramic discs, exact size contact pins and high grade tungsten filament wire. Special jigs are used to produce the exact shape of the tungsten filament and to precisely align it with the posts before it is welded and then annealed in high vacuum to reduce stress in the filament. This guarantees optimum stability and maximum brightness with a longer lifetime and lower running costs.

There are filaments available for most current and previous makes and models of electron microscopes, including Carl Zeiss, Coxem, Hitachi, JEOL, Pemtron, Tescan and ThermoFisher (FEI).

See also our range of Kimball Physics LaB6 cathodes as an alternative to a replacement tungsten filament.

Electron microscope type or filament base	Product number (click on number for details)	Ceramic disc mm	Pin diameter mm	Pin pitch mm
AEI	VS-AE-N-10	12.0	1.0	6.45
AmRay /AMR (except 1200 series)	AR-AMRE-N-10	26.0	1.0	5.0
Cambridge Instruments (except S4-10)	VS-AE-N-10	12.0	1.0	6.45
CamScan with AEI conversion	VS-AE-N-10	12.0	1.0	6.45
CamScan with new Tescan Column	VL-TE-N-10	19.8	1.0	5.0
Coxem	CL-ISIE-2-N-10	23.4	1.2	12.0
FEI	VL-PE-N-10	26.0	1.0	5.0
Hitachi S-Type	VL-HO-N-10	9.8	1.2	2.7
Hitachi with Cartridge TM series tabletop 3400N, 3700N, SU1500, SU3500	VL-HOC-N-10	9.8	1.2	2.7
ISI /ABT / Topcon 2-Pin	CL-ISIE-2-N-10	23.4	1.2	12.0
JEOL K-Type with metal ring	CL-JE-N-6	28.0	1.2	8.0
Leica	VS-AE-N-10	12.0	1.0	6.45
LEO 400 and 1400 Series SEM	VS-AE-N-10	12.0	1.0	6.45
LEO1450 (except AEI conversions)	VL-ZE-N-10	19.8	1.0	5.0
LEO TEM	VL-ZE-N-10	19.8	1.0	5.0
Pemtron	CL-ISIE-2-N-10	23.4	1.2	12.0
Philips V-Loop (PSEM500/EM200 and later)	VL-PE-N-10	26.0	1.0	5.0
Tescan	VL-TE-N-10	19.8	1.0	5.0
Zeiss DSM and TEM	VL-ZE-N-10	19.8	1.0	5.0
Zeiss EVO	VS-AE-N-10	12.0	1.0	6.45

The electron source performance table is provided to give additional information regarding the performance and requirements for different type of electron emitters. Tungsten cathodes are still used in the majority in SEMs and in general use TEMs. Improved results can be obtained with LaB6 cathodes, whereas the highest resolution can be obtained with either Schottky or cold Field Emission Sources which can only be used in suitable EMs.

Emitter Type	Thermionic	Thermionic	Schottky FE	Cold FE
Cathode Material	W	LaB6	ZrO/W (100)	W (310)
Operating Temp (K)	2700	1800	1800	300
Cathode Radius (nm)	60,000	10,000	<1000	<100
Effective Source Radius (µm)	25	10	0.015	0.0025
Emission Current Density (A/cm2)	3	30	5300	17,000
Total Emission Current (µA)	200	80	200	5
Brightness (A/cm2.sr.kV)	1×10⁴	1×10⁵	1×10⁷	2×10⁷
Maximum Probe Current (nA)	1000	1000	10	0.2
Energy Spread @ Cathode (ev)	0.59	0.4	0.31	0.26
Energy Spread @ Source Exit (eV)	1.5 – 2.5	1.3 – 2.5	0.35 – 0.7	0.3 – 0.7
Beam Noise (%)	1	1	1	5 – 10
Emission Current Drift (%/h)	0.1	0.2	<0.5	5
Operating Vacuum (hPa/mbar)	<10^-5	<10^-6	<10^-8	<10^-10
Typical Cathode Life (h)	100	>1000	>5000	>2000
Cathode Regeneration (h)	None	None	None	6-12
Sensitivity to External Influences	Minimal	Low	Low	High