Enhanced transmission line model structures for accurate resistance evaluation of small-size contacts and for more reliable fabrication
Article
Sawdai, D, Pavlidis, D, Cui, D. (1999). Enhanced transmission line model structures for accurate resistance evaluation of small-size contacts and for more reliable fabrication
. IEEE TRANSACTIONS ON ELECTRON DEVICES, 46(7), 1302-1311. 10.1109/16.772468
Sawdai, D, Pavlidis, D, Cui, D. (1999). Enhanced transmission line model structures for accurate resistance evaluation of small-size contacts and for more reliable fabrication
. IEEE TRANSACTIONS ON ELECTRON DEVICES, 46(7), 1302-1311. 10.1109/16.772468
Two new transmission line model (TLM) techniques are presented. The first structure, LT-TLM, provides very accurate determination of the transfer length LT (within 5%) and the contact resistivity ρC (within 12%) of lateral contacts, as compared to typical errors of 30 and 50%, respectively, for conventional TLM patterns. Accurate determination of these quantities is important for the optimal design of small lateral contacts in high-performance devices, such as heterojunction bipolar transistors (HBT's). The second structure, a modified concentric TLM pattern, provides the same results as conventional TLM patterns; however, they do not require mesa isolation, and they can be fabricated extremely reliably. In contrast, conventional concentric TLM patterns are often shorted together or distorted by lift-off metallization processes. Both theoretical analysis and experimental verification with analysis of the accuracy of the extracted data is presented for each technique, demonstrating the advantages of these approaches.
