| 摘要 |
<p>The present invention provides a method for manufacturing a dual work function semiconductor device. The method comprises:
providing a substrate (5) with a first region (I) and a second region (II);
forming a first control electrode stack on the first region (I), the first control electrode stack having a first effective work function, and forming a second control electrode stack on the second region (II), the second control electrode stack having a second effective work function, wherein each control electrode stack comprises a control electrode dielectric and a control electrode. The process of forming the control electrode stacks comprises:
(i) forming a host dielectric layer (1) overlying the first region (I) and the second region (II) of the substrate (5),
(ii) forming a first dielectric capping layer (2) overlying the host dielectric layer (1) on the first region (I) and on the second region (II), wherein the first dielectric capping layer is selected to determine the second effective work function,
(iii) removing at least the first dielectric capping layer (1) selectively to an underlying layer (1; 5) on the first region (I), thereby exposing the underlying layer (1; 5) on the first region (I),
(iv) forming a Hf-based dielectric capping layer (3) overlying the underlying layer (1; 5) on the first region and the first dielectric capping layer (2) on the second region (II), wherein the Hf-based dielectric capping layer (3) is selected to have a healing effect on the exposed surface of the underlying layer (1; 5) on the first region (I), and
(v) forming a control electrode (4) overlaying the Hf-based dielectric capping layer (3) on the first region (I) and on the second region (II).</p> |
