Improvement in noise characteristics of GaAsSb-based backward diodes by using a modified junction structure

Summary form only given. The noise performance was improved by modifying the junction structure of GaAsSb-based backward diodes for millimeter and terahertz wave detection. A noise equivalent power (NEP) of 64 pW/Hz
^1/2
at 300 GHz was achieved with diodes that consisted of a p
⁺
-GaAsSb/n-InGaAs heterojunction. This value was much lower than 303 pW/Hz
^1/2
that was obtained from the previously reported diodes consisting of a p
⁺
-GaAsSb/i-InAlAs/n-InGaAs heterojunction. The improvement in the NEP resulted from a considerable reduction in the junction resistance (R
_j
) from 17.9 MΩ to 0.41 MΩ by removing the thin i-InAlAs barrier layer. The modified GaAsSb-based backward diodes are applicable for millimeter and terahertz receiver applications.