Method of producing ceramic substrates

A method of producing a plurality of ceramic substrates by breaking a ceramic base plate,

• wherein said ceramic base plate comprises a plurality of substrate regions divided with each other, said substrate region comprising a corner part;
• wherein a dividing groove is formed between said substrate regions adjacent with each other;
• wherein said corner part of each of said substrate regions faces a spacing communicated with said dividing groove;
• wherein at least a part of said corner part is arc-shaped;
• and
• wherein said arc-shaped part of said corner part is tangent to a center line of said dividing groove at a cross point of said spacing with said dividing groove;
• the method comprising the step of producing said ceramic substrates by breaking said ceramic base plate along said dividing groove.