| 1. |
- Cha, Eunjung, et al.
(författare)
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Two-Finger InP HEMT Design for Stable Cryogenic Operation of Ultra-Low-Noise Ka-and Q-Band LNAs
- 2017
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Ingår i: IEEE transactions on microwave theory and techniques. - : Institute of Electrical and Electronics Engineers Inc.. - 0018-9480 .- 1557-9670. ; 65:12, s. 5171-5180
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the cryogenic stability of two-finger 100-nm gate-length InP HEMTs aimed for Ka-and Q-band ultra-low noise amplifiers (LNAs). InP HEMTs with unit gate widths ranging between 30 and 50 mu text{m} exhibit unstable cryogenic behavior with jumps in drain current and discontinuous peaks in transconductance. We also find that shorter gate length enhances the cryogenic instability. We demonstrate that the instability of two-finger transistors can be suppressed by either adding a source air bridge, connecting the back end of gates, or increasing the gate resistance. A three-stage 24-40 GHz and a four-stage 28-52-GHz monolithic microwave-integrated circuit LNA using the stabilized InP HEMTs are presented. The Ka-band amplifier achieves a minimum noise temperature of 7 K at 25.6 GHz with an average noise temperature of 10.6 K at an ambient temperature of 5.5 K. The amplifier gain is 29 dB ± 0.6 dB. The Q-band amplifier exhibits minimum noise temperature of 6.7 K at 32.8 GHz with average noise temperature of 10 K at ambient temperature of 5.5 K. The amplifier gain is 34 dB ± 0.8 dB. To our knowledge, the Ka-and Q-band amplifiers demonstrate the lowest noise temperature reported so far for InP cryogenic LNAs. © 1963-2012 IEEE.
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| 2. |
- Malm, B. Gunnar, 1972-, et al.
(författare)
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Bipolar technology
- 2016
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Ingår i: The VLSI Handbook: Second Edition. - : CRC Press. - 9781420005967 - 084934199X - 9781315222004 ; , s. 1.3-1.25
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 3. |
- Suvar, Erdal, et al.
(författare)
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Characterization of leakage current related to a selectively grown collector in SiGeC heterojunction bipolar transistor structure
- 2004
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332 .- 1873-5584. ; 224:1-4, s. 336-340
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Tidskriftsartikel (refereegranskat)abstract
- Sources of base-collector and base-emitter leakage current in a SiGeC-based heterojunction bipolar transistor (HBT) with a selectively grown and chemical-mechanical polished (CMP) collector are discussed. Transmission electron microscopy and electrical measurement have been applied to investigate the leakage current. It has been demonstrated that the edge-located defects generated by selective epitaxy process are the origin of the junction leakage.
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