The present analysis proposes a new technique to optimize the device parameters for improving the transconductance-to-current ratio of vertical surrounding gate (VSG) and double gate (DG) MOSFETs. Advantages of VSG MOSFETs over DG MOSFETs in terms of transconductance-to-current ratio (g(m)/I-ds) are examined in detail. Model shows new opportunities for realizing future ULSI circuits with VSG MOSFETs. Close proximity with published results confirms the validity of the present model. (C) 2002 Elsevier Science Ltd. All rights reserved.