Optimization of terahertz monolithic integrated frequency multiplier based on trap-assisted physics model of THz Schottky barrier varactor
Lu-Wei Qi(祁路伟)1,2,3, Jin Meng(孟进)2, Xiao-Yu Liu(刘晓宇)1, Yi Weng(翁祎)1, Zhi-Cheng Liu(刘志成)1, De-Hai Zhang(张德海)2,†, Jing-Tao Zhou(周静涛)1,‡, and Zhi Jin(金智)1
1Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China 2National Space Science Center, the Chinese Academy of Sciences, Beijing 100190, China 3University of Chinese Academy of Sciences, Beijing 100190, China
The optimization of high power terahertz monolithic integrated circuit (TMIC) is systemically studied based on the physical model of the Schottky barrier varactor (SBV) with interface defects and tunneling effect. An ultra-thin dielectric layer is added to describe the extra tunneling effect and the damping of thermionic emission current induced by the interface defects. Power consumption of the dielectric layer results in the decrease of capacitance modulation ration (Cmax/Cmin), and thus leads to poor nonlinear C–V characteristics. The proposed Schottky metal-brim (SMB) terminal structure could improve the capacitance modulation ration by reducing the influence of the interface charge and eliminating the fringing capacitance effect. Finally, a 215 GHz tripler TMIC is fabricated based on the SMB terminal structure. The output power is above 5 mW at 210–218 GHz and the maximum could exceed 10 mW at 216 GHz, which could be widely used in terahertz imaging, radiometers, and so on. This paper also provides theoretical support for the SMB structure to optimize the TMIC performance.
Lu-Wei Qi(祁路伟), Jin Meng(孟进), Xiao-Yu Liu(刘晓宇), Yi Weng(翁祎), Zhi-Cheng Liu(刘志成), De-Hai Zhang(张德海)†, Jing-Tao Zhou(周静涛)‡, and Zhi Jin(金智) Optimization of terahertz monolithic integrated frequency multiplier based on trap-assisted physics model of THz Schottky barrier varactor 2020 Chin. Phys. B 29 104212
Fig. 1.
(a) Optical microscopy image of a fabricated SBV. The SEM photographs of Schottky metal-brim structure details are added. (b) SBV with Schottky metal-brim. (c) Conventional SBV.
Fig. 2.
Energy band diagram of MIS structure.
Fig. 3.
(a) Forward I–V characteristics with different structures in log scale (similar with diameter @3 μm). (b) Reverse breakdown characteristics with different structures.
Parameter
Value
Dielectric-layer thickness δ/nm
0.256
Interface acceptor density Dit/cm2⋅eV
2.7 × 1012
Dielectric constant[21]
4.0
Capacitance ideal coefficient η
0.7
Correction term D1
0.36
Table 1.
Key parameters of the modified model.
Fig. 4.
Comparison of the measured C–V curves of the SMB-SBV structure and simulated curves based on different models.
Fig. 5.
Equivalent circuit of the 215 GHz TMIC tripler.
Fig. 6.
(a) SEM image of a fabricated tripler TMIC chip. (b) SEM image of a pair of varactors in parallel.
Fig. 7.
Photo of test-site about 215 GHz tripler TMIC.
Fig. 8.
(a) Measured input and output power as a function of frequency. (b) Measured output power and efficiency as a function of input power at different frequency.
Fig. 9.
Comparison of the measured efficiency and simulated curves based on different physics-based C–V models.
References
Technology
Frequency/GHz
Max output power/mW
Efficiency
UESTC[27]
Tripler TMIC
330–500
0.19
2%(max)
ICET[28]
Membrane tripler TMIC
430
0.215
4.3%(max)
VDI[29]
Tripler TMIC
140–220
–
3%(typical)
CETC[30]
Tripler TMIC
325–500
0.45
4.4%(max)
This paper
SMB-structure tripler TMIC
215
10.2
4.5%(max)
Table 2.
Performance comparison of the frequency multipliers based on TMIC.
Anwar M, Dhar N K, Crowe T W 2010 Terahertz Physics, Devices, and Systems IV: Advanced Applications in Industry and Defense 7671 DOI: 10.1117/12.865882
[4]
Lancaster M J, Guo C, Powell J 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) 1-1 DOI: 10.1109/IRMMW-THz.2019.8874014
[5]
Gatilova L, Maestrini A, Treuttel J 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves 1 2 DOI: 10.1109/IRMMW-THz.2019.8873728
[6]
Crowe T W, Hesler J L, Porterfield D W 2007 Joint 32nd International Conference on Infrared and Millimeter Waves and the 15th International Conference on Terahertz Electronics 621 DOI: 10.1109/ICIMW.2007.4516653
[7]
Amir F, Mitchell C, Missous M 2010 The Eighth International Conference on Advanced Semiconductor Devices and Microsystems 29 DOI: 10.1109/ASDAM.2010.5667005
[8]
Ding J Q, Maestrini A, Gatilova L 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves 1 2 DOI: 10.1109/IRMMW-THz.2019.8873979
Perez-Moreno C G, Grajal J, Viegas C 2016 Global Symposium on Millimeter Waves (GSMM) & ESA Workshop on Millimetre-Wave Technology and Applications 1 DOI: 10.1109/GSMM.2016.7500307
[12]
Kolberg E L, Tolmunen T J, Frerking M A 1992 IEEE Trans. Microwave Theory Tech. 40 831 DOI: 10.1109/22.137387
[13]
Kiuru T, Mallat J, Raisanen A V 2011 IEEE Trans. Microwave Theory Tech. 59 2108 DOI: 10.1109/TMTT.2011.2146268
[14]
Moro-Melgar D, Maestrini A, Treuttel J 2016 IEEE Trans. Electron Devices 63 3900 DOI: 10.1109/TED.2016.2601341
[15]
Ren T, Zhang Y 2017 IEEE MTT-S International Microwave Symposium (IMS) 2003 DOI: 10.1109/MWSYM.2017.8059060
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