High-temperature superconducting edge-type Josephson junctions with modified interfaces

A new process is presented for fabricating uniform high-temperature superconducting edge-type Josephson junctions. The junctions were fabricated by an in situ process using low-/spl epsi/ LaSrAlTaO material for both the insulator layer and the substrate. The LaSrAlTaO layer played a role as a mask for in situ edge fabrication. This process contained no intentional barrier deposition process. These junctions however showed resistively and capacitively shunted junction like current-voltage characteristics and an excellent uniformity. These junctions showed small spreads in the critical current as low as 1 /spl sigma/=8% for 100 junctions at 4.2 K.