Denka TFE (Thermal Field Emitter)

Overview

DENKA TFE is a high performance ZrO/W emitter on tungsten with decreased work functions. Due to its brightness, which is 100 times higher than monocrystalline LaB6 cathodes, the DENKA TFE is most suitable for surface observation of materials and devices. In addition to high resolution imaging at lower accelerating voltages, the Denka TFE has an extremely stable emission current and long lifetime. The DENKA TFE is used in various electron beam application equipment such as semiconductor inspectors and electron beam lithography systems. A field emission emitter produces an electron beam that is smaller in diameter, more coherent and provides up to three orders of magnitude greater current density or brightness than can be achieved with conventional thermionic emitters. The result in both scanning and transmission electron microscopy is significantly improved signal-to-noise ratio and spatial resolution, and greatly increased emitter life and reliability compared with thermionic devices. Denka has a long standing history of providing reliable and quality products. The following is a technical drawing of the Denka emitter:

• Operating temperature: ≤ 1850K. 1800K recommended.
• Operating pressure: ≤ 1.3x10-6Pa (1x10-8Torr).
• Operation ≤ 2.7x10-7Pa (2x10-9Torr) recommended.
• Tip radius: 0.3 to 0.9μm. Range of tolerance ΔR=0.1 or 0.2μm. Remark: For tip radius range >
• 0.9μm, contact
• Filament current at 1800K:≤ 2.6A

Rave Scientific offers two types of Denka emitters: The 174 and the 174 C. The 174 has a .6 micron tip +/- .1 micron and is applicable for high resolution low KeV performance and applications that require more current stability such as E-Beam Lithography and EDS. The 174C has a tip diameter of about .3 micron +/- .1 Micron and traditionally has been used in TEM systems or in situations where an end user is requiring higher brightness or slightly better imaging performance.