Normally-off JFETs with 1.3 ?m-long gates were fabricated by selective double ion implantation for the n and n+ regions and selective Zn diffusion for the p-gate area. A JFET with a 10 ?m-wide gate had a transconductance of 2 mS in average and a high value of 3 mS. A 15 stage ring oscillator made of resistively loaded DCFLs showed the minimum delay time of 45 ps, the shortest value obtained based on optical lithography. The minimum power-delay product was 3.8 fJ with a delay time of 83 ps.