Thermal airflow sensor
A thermal airflow sensor includes a semiconductor device, a protective film a bonding wire, and a resin. The resin covers over a part of the semiconductor device so that the bonding wire is covered with the resin and the region including a thin-wall portion is exposed. The protective film is not covered with the resin and has an outer peripheral edge located outside the thin-wall portion.
1. A thermal airflow sensor comprising:
a semiconductor device having a thin-wall portion on which a heating resistor and resistance temperature detectors are provided;
a protective film formed on a surface of the semiconductor substrate so that the heating resistor is exposed;
a bonding wire connected to the semiconductor device electrically;
a resin that covers over a part of the semiconductor device so that the bonding wire is covered with the resin and the region including the thin-wall portion is exposed;
wherein the protective film has multiple slits between the region covered with the resin and the thin-wall portion.
2. The thermal airflow sensor according to claim 1 , further comprising:
a resistor formed over semiconductor substrate;
wherein the slits are formed so as to expose the resistor.