Semiconductor device having integrated diode

A semiconductor device comprising:

• a body of semiconductor material having first and second major opposing surfaces;
• a first region within said body having one type conductivity, said first region being adjacent said second surface;
• a second region within said body adjacent said first surface having a second type conductivity and forming a first PN junction with said first region at the interface therebetween, said first PN junction having a positionally dependent breakdown voltage associated therewith and having a point of lowest value of breakdown voltage therealong;
• said second region comprising a relatively thicker portion and a relatively thinner portion, said relatively thicker portion substantially completely peripherally surrounding said relatively thinner portion;
• said second region having a surface impurity concentration on the order of about 10.sup.17 carriers/cm.sup.3, said relatively thicker portion extends to a depth of about 60 micrometers from said first surface;
• and
• said relatively thinner portion extending to a depth of about 30 micrometers from said first surface;
• a third region having said one type conductivity adjacent said first surface and extending into said second region, said third region forming a second PN junction with said second region at the interface therewith;
• said third region extending into said relatively thicker portion of said second region and substantially completely peripherally surrounding said relatively thinner portion;
• and
• a first electrode overlying and electrically contacting said third region and the portion of said second region overlying said point of lowest value.