| 摘要 |
PURPOSE: A device and a method using trench isolation are provided without a void in a trench isolation region with high aspect ratio and without a dent between the isolation region and an active region. CONSTITUTION: In the semiconductor device, the trench isolation region(20) having a bottom surface(20a) and a sidewall(20b) is formed in a silicon substrate(10) to divide adjacent two active regions. A silicon epitaxial layer(30) is in contact with the silicon substrate(10) at the bottom surface(20a) and fills the lower half of the trench isolation region(20). The first oxide layer(40) extends along the sidewall(20b) to a portion of the bottom surface(20a) in L-shaped profile. Further, an oxidation-proof liner(50) is formed in L-shaped profile between the first oxide layer(40) and the epitaxial layer(30), having a surface(50a) adjoining the epitaxial layer(30). In particular, the oxidation-proof liner(50) has a thickness(d) of about 50-70Å, preferably about 55-65Å. Such a smaller thickness(d) results in a minimum etching by wet loading effect, thereby preventing a dent due to etching of the liner(50). The second oxide layer(60) is formed on the epitaxial layer(30) to fill the upper half of the trench isolation region(20).
|
