• 제목/요약/키워드: POSTECH

Search Result 1,873, Processing Time 0.03 seconds

Design of High Average Power Pulse Transformer for 30-MW Klystron of L-Band Linac Application (산업용 선형가속기 시스템 적용을 위한 30-MW 클라이스트론용 고 평균전력 펄스 트랜스포머의 설계)

  • Jang, S.D.;Son, Y.G.;Gwon, S.J.;Oh, J.S.;Bae, Y.S.;Lee, H.G.;Moon, S.I.;Kim, S.H.;Cho, M.H.;NamKung, W.
    • Proceedings of the KIEE Conference
    • /
    • 2006.07c
    • /
    • pp.1550-1551
    • /
    • 2006

  • An L-band linear accelerator system for e-beam sterilization is under design for bio-technology application. The klystron-modulator system as RF microwave source has an important role as major components to offer the system reliability for long time steady state operation. A PFN line type pulse generator with a peak power of 71.5-MW, $7{\mu}s$, 285 pps is required to drive a high-power klystron. The high power pulse transformer has a function of transferring pulse energy from a pulsed power source to a high power load. The pulse transformer producing a pulse with a peak voltage of 275 kV is required to produce 30-MW peak and 60 kW average RF output power at the frequency of 1.3-GHz. We have designed the high power pulse transformer with 1:13 step-up ratio. The peak and average power capability is 71.5-MW (275 kV, 260 A at load side with $7{\mu}s$ pulse width) and 130 kW, respectively. In this paper, we present a system overview and initial design results of the high power pulse transformer.

  • PDF

Optimization of Ar Reshape Process for 4H-SiC Trench MOSFET (4H-SiC Trench MOSFET 응용을 위한 Ar Reshape 공정 최적화)

  • Sung, Min-Je;Kang, Min-Jae;Kim, Hong-Ki;Kim, Seong-jun;Lee, Jung-Yoon;Lee, Wonbeom;Lee, Nam-suk;Shin, Hoon-Kyu
    • Journal of IKEEE
    • /
    • v.22 no.4
    • /
    • pp.1234-1237
    • /
    • 2018

  • For 4H-SiC trench MOSFET which can reduce on-resistance and switching losses compared to 4H-SiC planar MOSFET, the optimization study for decrease of sub-trench was carried out. In order to decrease sub-trench, Ar reshape process was used and trench shapes were observed as a function of temperature and process time. As a result, it was confirmed that the process conditions for $1500^{\circ}C$ and 20 min were most effective for the suitable trench profiles. In addition, dry/wet oxidation was performed at the Ar reshaped-samples to observe the oxidation thickness with different crystal orientations.

  • https://doi.org/10.7471/ikeee.2018.22.4.1234 인용 PDF KSCI HTML