CMOS-compatible power MOSFETs for on-chip DC/DC converters

This thesis deals with low-voltage power MOSFETs which are used in portable, high-efficiency switch mode DC/DC converters for personal digital assistants (PDA's) applications. Two power MOSFETs based on lateral, low-voltage CMOS processes and capable of carrying 1 A of current in the on-state are investigated in this thesis.; The first device uses a 0.8 mum single level metallization CMOS process. The unit cell pitch of the MOSFET switch is 4.1 mum using a channel length of 0.8 mum. The layout of a power switch with 1 A current carrying capability uses a checkerboard pattern to maximize the channel width per unit area resulting in a total active chip area of 290 x 290 mum2 corresponding to a total channel width of 31,878 mum.; The second device uses a 0.25 mum - 5 level metallization commercial CMOS process. Experimental results for the 0.25 mum switch show significant performance improvement over the 0.8 mum design. The layout of the switch utilizes a checkerboard pattern resulting in an active chip area of 130 x 130 mum2 corresponding to a total channel width of 12,499 mum. (Abstract shortened by UMI.)...