Method of fusing trimming for semiconductor device

1. A fuse trimming method for a semiconductor device in which circuit elements such as transistors and resistors are formed on a semiconductor wafer and which includes fuse elements capable of adjusting a resistance value of the resistors by laser trimming, the fuse trimming method comprising:

a resistor correction step of correcting in a particular region of the semiconductor wafer the resistance value of the resistors based on an amount of deviation from a target value of the resistance value of the resistors, the resistor correction step comprising the steps of:

conducting a first electric characteristic test on a semiconductor device that is formed on a first semiconductor wafer;

calculating first trimming data from data of the first electric characteristic test;

using the first trimming data to cut off a fuse in the semiconductor device formed on the first semiconductor wafer;

conducting a second electric characteristic test on the semiconductor device from which the fuse has been cut;

calculating relative accuracy from data of the second electric characteristic test;

dividing the first wafer into a first region that has a semiconductor device whose relative accuracy is within tolerance and a second region that has a semiconductor device whose relative accuracy is outside the tolerance, and calculating a mean relative accuracy of each of the first region and the second region;

calculating a correction coefficient for each region from the mean relative accuracy of each of the first region and the second region;

conducting the first electric characteristic test on a semiconductor device that is formed on a second semiconductor wafer;

calculating second trimming data based on the correction coefficient of each of the first region and the second region in addition to the data of the first electric characteristic test of the semiconductor device formed on the second semiconductor wafer; and

using the second trimming data to cut off a fuse in the semiconductor device formed on the second semiconductor wafer.

2. A fuse trimming method for a semiconductor device according to claim 1 ; wherein the first semiconductor wafer comprises a first wafer in a wafer lot, and the second semiconductor wafer comprises one of a second wafer and subsequent semiconductor wafers in the wafer lot.

3. A fuse trimming method for a semiconductor device according to claim 1 ; wherein the first semiconductor wafer comprises the first several wafers in a wafer lot, and the second semiconductor wafer comprises a semiconductor wafer that follows the first semiconductor wafer in the wafer lot.

4. A fuse trimming method for a semiconductor device according to claim 1 ; wherein the first semiconductor wafer and the second semiconductor wafer constitute different wafer lots.