MANUFACTURING METHOD OF FLASH MEMORY AND TRANSISTOR

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method of a flash memory and a transistor in which the concentration gradient of dopant at a joint part is gentle in a source region while steep in a drain region. SOLUTION: There are provided a step in which a gate 14 is formed on a substrate, a step in which a first dopant is injected into a source formation region, a step in which a dielectric spacer 40 is formed on a side wall part of the gate 14, a step in which a second dopant whose dispersion characteristics is lower than the first dopant is injected into a drain formation region, and a step in which a source region 20-2 and a drain region 22-2 are formed in a thermal dispersion process.