Method of producing a semiconductor device semiconductor device having a field termination structure and a charge balance structure

A method of producing a semiconductor device, the method comprising:

• forming an active device region and a termination region in a semiconductor substrate, the active device region including a plurality of device cells, the termination region being disposed between the active device region and an edge of the semiconductor substrate;
• forming a field termination structure in the termination region, the field termination structure comprising a continuous region of a first conductivity type and a plurality of rings of the first conductivity type in the continuous region and having a higher average doping concentration than the continuous region;
• and
• forming a charge balance structure in the active device region, the charge balance structure comprising interleaved columns of the first conductivity type and of a second conductivity type opposite the first conductivity type,
• wherein at least part of the charge balance structure extends into the termination region below the field termination structure such that at least one of the columns of the first conductivity type is connected to the continuous region of the field termination structure,
• wherein a plurality of the columns of the first conductivity type is disposed below the field termination structure and electrically connected to the plurality of the rings of the first conductivity type,
• wherein a width and/or an average doping concentration of the plurality of the columns of the first conductivity type disposed below the field termination structure decreases in a horizontal direction heading towards the edge of the semiconductor substrate.

A method of producing a semiconductor device, the method comprising:

• forming an active device region and a termination region in a semiconductor substrate, the active device region including a plurality of device cells, the termination region being disposed between the active device region and an edge of the semiconductor substrate;
• forming a field termination structure in the termination region, the field termination structure comprising a continuous region of a first conductivity type and a plurality of rings of the first conductivity type in the continuous region and having a higher average doping concentration than the continuous region;
• and
• forming a charge balance structure in the active device region, the charge balance structure comprising interleaved columns of the first conductivity type and of a second conductivity type opposite the first conductivity type,
• wherein at least part of the charge balance structure extends into the termination region below the field termination structure such that at least one of the columns of the first conductivity type is connected to the continuous region of the field termination structure,
• wherein forming the charge balance structure comprises:
• doping an upper part of the columns of the first conductivity type more heavily than an adjacent upper part of the columns of the second conductivity type;
• and
• doping a lower part of the columns of the first conductivity type more lightly than an adjacent lower part of the columns of the second conductivity type.

A method of producing a semiconductor device, the method comprising:

• forming an active device region and a termination region in a semiconductor substrate, the active device region including a plurality of device cells, the termination region being disposed between the active device region and an edge of the semiconductor substrate;
• forming a junction termination extension of a first conductivity type in the termination region;
• forming a field termination structure in the termination region, the field termination structure comprising a continuous region of the first conductivity type and a plurality of rings of the first conductivity type in the continuous region and having a higher average doping concentration than the continuous region;
• and
• forming a charge balance structure in the active device region, the charge balance structure comprising interleaved columns of the first conductivity type and of a second conductivity type opposite the first conductivity type,
• wherein the charge balance structure extends into the termination region below the junction termination extension,
• wherein a depth of the interleaved columns of the charge balance structure disposed below the junction termination extension decreases in a horizontal direction heading towards the edge of the SiC substrate,
• wherein the charge balance structure extends below the field termination structure such that at least an outermost one of the columns of the first conductivity type is connected to the continuous region of the field termination structure,
• wherein the columns of the first and/or second conductivity type in the active device region have a different doping profile than each column of the same conductivity type disposed below the field termination structure.

A method of producing a semiconductor device, the method comprising:

• forming an active device region and a termination region in a semiconductor substrate, the active device region including a plurality of device cells, the termination region being disposed between the active device region and an edge of the semiconductor substrate;
• forming a field termination structure in the termination region, the field termination structure comprising a continuous region of a first conductivity type and a plurality of rings of the first conductivity type in the continuous region and having a higher average doping concentration than the continuous region;
• and
• forming a charge balance structure in the active device region, the charge balance structure comprising interleaved columns of the first conductivity type and of a second conductivity type opposite the first conductivity type,
• wherein the charge balance structure extends into the termination region below the field termination structure such that at least an outermost one of the columns of the first conductivity type is connected to the continuous region of the field termination structure,
• wherein the continuous region extends deeper into the semiconductor substrate than the plurality of rings of the first conductivity type,
• wherein the field termination structure comprises a plurality of rings of the second conductivity type in the continuous region and interleaved with the plurality of rings of the first conductivity type.