A semiconductor device includes a first transistor, a second transistor, and a memory component. The first transistor includes a first silicon layer, a high-k gate dielectric layer above the first silicon layer, a first metal gate above the high-k gate dielectric layer, and first source/drain regions within the first silicon layer. The second transistor includes a second silicon layer, a first silicon oxide layer above the second silicon layer, a plurality of first doped silicon gates above the first silicon oxide layer, a plurality of second doped silicon gates above the first silicon oxide layer and alternately arranged with the plurality of first doped silicon gates, and second source/drain regions within the second silicon layer. The memory component is above the first and second transistors, and electrically coupled to the second source or drain region.