Method of forming semiconductor structure
A method of forming a semiconductor structure is provided. A substrate having a cell area and a periphery area is provided. A stacked structure including a gate oxide layer, a floating gate and a first spacer is formed on the substrate in the cell area and a resistor is formed on the substrate in the periphery area. At least two doped regions are formed in the substrate beside the stacked structure. A dielectric material layer and a conductive material layer are sequentially formed on the substrate. A patterned photoresist layer is formed on the substrate to cover the stacked structure and a portion of the resistor. The dielectric material layer and the conductive material layer not covered by the patterned photoresist layer are removed, so as to form an inter-gate dielectric layer and a control gate on the stacked structure, and simultaneously form a salicide block layer on the resistor.
1. A method of forming a semiconductor structure, comprising:
providing a substrate, wherein the substrate has a cell area and a periphery area;
forming a stacked structure on the substrate in the cell area and forming a resistor on the substrate in the periphery area, wherein the stacked structure comprises a gate oxide layer, a floating gate and a first spacer;
forming at least two doped regions in the substrate beside the stacked structure;
sequentially forming a dielectric material layer and a conductive material layer on the substrate;
forming a patterned photoresist layer on the conductive material layer;
removing the dielectric material layer and the conductive material layer not covered by the patterned photoresist layer, so as to form an inter-gate dielectric layer and a control gate on the stacked structure and simultaneously form a salicide block (SAB) layer on the resistor, wherein the gate oxide layer, the floating gate, the inter-gate dielectric layer and the control gate forms a charge storage structure;
forming a second spacer on a sidewall of the charge storage structure and on a sidewall of the SAB layer; and
forming a salicide layer on a surface of the control gate of the charge storage structure, on surfaces of doped regions, and on a surface of the resistor not covered by the SAB layer.
2. The method of claim 1 , wherein a material of the salicide layer comprises cobalt silicide.
3. The method of claim 1 , wherein a select transistor is simultaneously formed at a side of the stacked structure on the substrate in the cell area during the step of forming the stacked structure and the resistor, and wherein the doped regions are further formed in the substrate beside the select transistor, the charge storage structure and the select transistor share one doped region.
4. The method of claim 1 , wherein a material of the conductive material layer comprises doped polysilicon.