Semiconductor device with grooved die pad

A semiconductor device, comprising:

• a frame including a die pad and terminals extending away from the die pad in a first direction;
• a groove in an upper surface of the die pad, the groove extending lengthwise in the first direction and including a first groove portion and a second groove portion adjacent to each other in the first direction, the first groove portion being continuous with the second groove portion in the first direction;
• a semiconductor element on the upper surface of the die pad but not overlapping the groove;
• and
• a resin material in the groove and covering the semiconductor element, wherein the groove has a bottom surface and a first irregularity is formed in the bottom surface,
• the second groove portion has a width in a second direction perpendicular to the first direction that is greater than a width of the first groove portion,
• the length of the first groove portion in the first direction is greater than the length of the second groove portion in the first direction;
• the groove is proximate to an outer edge of the die pad, the outer edge extending in the first direction, and
• the groove extends the entire length of the die pad in the first direction.