Semiconductor device and related fabrication methods
View Patent ↗Semiconductor device structures and related fabrication methods are provided. An exemplary semiconductor device structure ( 100 ) includes a trench gate structure ( 114 ), a lateral gate structure ( 118 ), a body region ( 124 ) having a first conductivity type, a drain region ( 125 ) and first and second source regions ( 128, 130 ) having a second conductivity type. The first and second source regions ( 128, 130 ) are formed within the body region ( 124 ). The drain region ( 125 ) is adjacent to the body region ( 124 ) and the first source region ( 128 ) is adjacent to the trench gate structure ( 114 ), wherein a first portion of the body region ( 124 ) disposed between the first source region ( 128 ) and the drain region ( 125 ) is adjacent to the trench gate structure ( 114 ). A second portion of the body region ( 124 ) is disposed between the second source region ( 130 ) and the drain region ( 125 ), and the lateral gate structure ( 118 ) is disposed overlying the second portion of the body region ( 124 ).
1. A semiconductor device structure comprising:
a trench gate structure;
a lateral gate structure;
a body region of semiconductor material having a first conductivity type;
a first source region of semiconductor material having a second conductivity type, the first source region being formed within the body region adjacent to the trench gate structure;
a second source region of semiconductor material having the second conductivity type, the second source region being formed within the body region;
a drain region of semiconductor material having the second conductivity type, the drain region being adjacent to the body region, wherein:
a first portion of the body region disposed between the first source region and the drain region is adjacent to the trench gate structure; and
the lateral gate structure overlies a second portion of the body region disposed between the second source region and the drain region.
2. The semiconductor device structure of claim 1 , wherein a first portion of the drain region is adjacent to the trench gate structure, the first portion of the body region overlying the first portion of the drain region.
3. The semiconductor device structure of claim 2 , wherein the first source region overlies the first portion of the body region, the first portion of the body region being disposed between the first portion of the drain region and the first source region.
4. The semiconductor device structure of claim 2 , wherein a second portion of the drain region is adjacent to the lateral gate structure, the lateral gate structure overlying the second portion of the drain region, the second portion of the body region being disposed between the second portion of the drain region and the second source region.
5. The semiconductor device structure of claim 4 , wherein:
the trench gate structure and the lateral gate structure are electrically connected to provide a gate terminal for the semiconductor device structure; and
an electrical potential applied to the gate terminal results in a vertical conductive channel in the first portion of the body region between the first portion of the drain region and the first source region and a horizontal conductive channel in the second portion of the body region between the second portion of the drain region and the second source region.
6. The semiconductor device structure of claim 1 , wherein a third portion of the body region is disposed between the first portion and the second portion.
7. The semiconductor device structure of claim 1 , wherein the second source region is adjacent to the lateral gate structure.
8. The semiconductor device structure of claim 1 , wherein the trench gate structure and the lateral gate structure are electrically connected.
9. A method for fabricating a semiconductor device structure, the method comprising:
forming a voided region in a first region of semiconductor material having a first conductivity type;
forming a first gate structure in the voided region;
forming a second gate structure overlying the first region;
forming a second region of semiconductor material having a second conductivity type within the first region of semiconductor material, wherein a first portion of the second region is adjacent to the first gate structure and a second portion of the second region is underlying the second gate structure;
forming a third region of semiconductor material having the first conductivity type within the second region adjacent to the first gate structure, the third region overlying the first portion of the second region;
forming a fourth region of semiconductor material having the first conductivity type within the second region, the fourth region being adjacent to the second portion of the second region.
10. The method of claim 9 , wherein:
the first region comprises a drain/source region having the first conductivity type;
forming the second region comprises forming a body region having the second conductivity type within the drain/source region;
forming the third region comprises forming a first source/drain region having the first conductivity type within the body region adjacent to the first gate structure; and
forming the fourth region comprises forming a second source/drain region having the first conductivity type within the body region.
11. The method of claim 9 , wherein forming the second gate structure comprises:
forming a layer of conductive material overlying the first region; and
removing a portion of the layer of conductive material to expose a first portion of the first region, the first portion being adjacent to the first gate structure.
12. The method of claim 9 , wherein forming the second region comprises performing a chain implant to form a plurality of enhancement regions within the second region.
13. The method of claim 9 , wherein:
forming the third region comprises implanting ions of the first conductivity-determining impurity type in the first portion of the second region; and
forming the fourth region comprises implanting ions of the first conductivity-determining impurity type in the second portion of the second region.
14. The method of claim 13 , further comprising forming an implantation mask overlying a central portion of the second region, wherein:
forming the third region comprises implanting ions of a first conductivity-determining impurity type in the first portion using the implantation mask; and
forming the fourth region comprises implanting ions of the first conductivity-determining impurity type in the second portion using the implantation mask concurrently to implanting ions of the first conductivity-determining impurity type in the first portion.
15. The method of claim 9 , wherein forming the first gate structure comprises:
forming a layer of dielectric material in the voided region; and
forming a layer of conductive material in the voided region after forming the layer of dielectric material, the layer of dielectric material being disposed between the layer of conductive material and the first region.
16. The method of claim 9 , further comprising forming a region of conductive material in contact with the first gate structure and the second gate structure to provide an electrical connection between the first gate structure and the second gate structure.
17. The method of claim 9 , further comprising forming a layer of conductive material overlying and in contact with the second region, the third region, and the fourth region to provide an electrical connection between the second region, the third region, and the fourth region.
18. A semiconductor device structure comprising:
a first transistor structure comprising:
a trench gate structure;
a drain region of semiconductor material having a first conductivity type;
a body region of semiconductor material having a second conductivity type, the body region overlying the drain region adjacent to the trench gate structure; and
a first source region of semiconductor material having the first conductivity type, the first source region being formed within the body region adjacent to the trench gate structure; and
a second transistor structure comprising:
a lateral gate structure overlying a first portion of the drain region and a first portion of the body region, the first portion of the drain region being adjacent to the lateral gate structure; and
a second source region of semiconductor material having the first conductivity type, the second source region being formed within the body region, wherein the first portion of the body region is disposed between the second source region and the first portion of the drain region.
19. The semiconductor device structure of claim 18 , further comprising a region of conductive material in contact with the trench gate structure and the lateral gate structure.
20. The semiconductor device structure of claim 18 , further comprising a conductive material in contact with the first source region, the second source region, and the body region.