US Patent 7763928 Multi-time programmable memory

A multi-time programmable (MTP) memory includes a tunneling dielectric layer, a floating gate, an inter-gate dielectric layer and a control gate. The tunneling dielectric layer is disposed on a substrate. The floating gate is disposed on the tunneling dielectric layer. The inter-gate dielectric layer is disposed on the floating gate, and a thickness of the inter-gate dielectric layer at edges of the floating gate is larger than a thickness of the inter-gate dielectric layer in a central portion of the floating gate. The control gate is disposed on the inter-gate dielectric layer.