Study and design of a lens-type retarding field energy analyzer without a grid electrode

• Published in: Ultramicroscopy 2020-02, Vol.209, p.112880-112880, Article 112880
• Main Authors: Hwang, Junhyeok, Kim, Kwang-Il, Ogawa, Takashi, Cho, Boklae, Kim, Dong-Hyun, Park, In-Yong
• Format: Article
• Language: English
• Subjects: Cylinder lens; Einzel lens; Energy distribution; Retarding field energy analyzer; Sagging effect
• ISSN: 0304-3991; 1879-2723
• DOI: 10.1016/j.ultramic.2019.112880

•Lens-based RFEAs without a grid electrode were investigated.•Proposed design of RFEA is simulated and calculated for defining the energy resolution.•The resolution of 2.6 meV is achieved at an energy of 500 eV on the geometry and lens conditions.•To realize a high-resolution RFEA design, important factor is reducing the sagging effect.•The resolution and measurement error of three different lens-type RFEAs are compared. A retarding field energy analyzer (RFEA) for measuring the energy distribution of charged particles offers the advantages of a simple structure and suitability for simultaneous observations of beam patterns in two dimensions. In this study, lens-based RFEAs without a grid electrode were theoretically investigated with regard to the geometry and lens condition to achieve high performance. The simulation results show that the proposed RFEA can achieve a resolution of 2.6 meV at an energy level of 500 eV. In addition, performance, which is the ratio of the resolution to the beam energy, reached 5.2×10−6. These results indicate that the RFEA designed in this study is capable of high-performance outcomes. The findings here demonstrate that the most important factors when attempting to realize a high-resolution RFEA design are to reduce the sagging effect of the electron beam through the focusing lens and ensure that V″(z) in the retarding electrode is close to zero. The design of the lens-based RFEAs is described in detail.