Manufacturing Method for High Voltage Transistor
AssigneeMacronix International Co., Ltd.
InventorsYu-Hsien Chin, Chih-Chia Hsu, Yin-Fu Huang
Life of this patent
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Abstract
A manufacturing method for a high voltage transistor includes the following steps. A substrate is provided. A P-type epitaxial (P-epi) layer is provided above the substrate. An N-well is formed in the P-epi layer. A P-well is formed in the P-epi layer. Field oxide (FOX) layers are formed above the P-epi layer. A gate oxide (GOX) layer is formed between the FOX layers. P-type implants are doped into the P-well or N-type implants are doped into the N-well to adjust an electrical function of the high voltage transistor.
Claims10
A manufacturing method for a high voltage transistor, the method comprising the steps of:
- providing a substrate;
- providing a P-type epitaxial (P-epi) layer above the substrate;
- forming an N-well in the P-epi layer;
- forming a P-well in the P-epi layer;
- forming a plurality of field oxide (FOX) layers above the P-epi layer, wherein a flat surface of the P-well is exposed by one of the FOX layers;
- forming a gate oxide (GOX) layer between the FOX layers;
- and
- doping P-type implants into the P-well to adjust an electrical function of the high voltage transistor, wherein the P-type implants are disposed at whole of the flat surface of the P-well.
10-18. (canceled)
Dependencies are inferred from the claim text.