SPLIT GATE CHARGE TRAPPING MEMORY CELLS HAVING DIFFERENT SELECT GATE AND MEMORY GATE HEIGHTS

A semiconductor device and method of making such device is presented herein. The method includes disposing a gate layer over a dielectric layer on a substrate and further disposing a cap layer over the gate layer. A first transistor gate is defined having an initial thickness substantially equal to a combined thickness of the cap layer and the gate layer. A first doped region is formed in the substrate adjacent to the first transistor gate. The cap layer is subsequently removed and a second transistor gate is defined having a thickness substantially equal to the thickness of the gate layer. Afterwards, a second doped region is formed in the substrate adjacent to the second transistor gate. The first doped region extends deeper in the substrate than the second doped region, and a final thickness of the first transistor gate is substantially equal to the thickness of the second transistor gate.