0.5-μm 2 M-transistor BiPNMOS channelless gate array

A channelless gate array has been realized using 0.5-μm BiCMOS technology integrating more than two million transistors on a 14-mm×14.4-mm chip. A small-size PMOS transistor and a small-size inverter are added to the conventional BiNMOS gate to form the BiPNMOS gate. The gate is suitable for 3.3-V supply and achieves 230-ps gate delay for a two-input NAND with full-swing output. Added small-size MOS transistors in the BiPNMOS basic cell can also be used for memory macros effectively. A test chip with four memory macros-a high-speed RAM, a high-density RAM, a ROM, and a CAM macro-was fabricated. The high-speed memory macros utilize bipolar transistors in bipolar middle buffers and in sense amplifiers. The high-speed RAM macro achieves an access time of 2.7 ns at 16-kb capacity. The high-density RAM macro is rather slow but the memory cell occupies only a half of the BiPNMOS basic cell using a single-port memory cell