Electronic device comprising transistors
The present description concerns an electronic device comprising a semiconductor substrate, transistors having their gates contained in first trenches extending in the substrate, and at least one electronic component, different from a transistor, at least partly formed in a first semiconductor region contained in a second trench extending in the semiconductor substrate parallel to the first trenches.
1 . An electronic device comprising:
a semiconductor substrate;
a first trench and a second trench extending in the semiconductor substrate, the first trench and the second trench are parallel to one another;
a first electrically insulating layer in the second trench and partially filling the second trench;
a first electrically-conductive element in the second trench, on the first electrically insulating layer, and partially filling the second trench, the first electrically-conductive element is separated from the semiconductor substrate by the first electrically insulating layer;
a second electrically insulating layer in the second trench, on the first electrically-conductive element, and partially filling the second trench;
a first semiconductor region recessed into the first electrically-conductive element within the second trench, the first semiconductor region is on the second electrically insulating layer, and the first semiconductor region has a first conductivity type, the first semiconductor region contacts the first electrically insulating layer and the second electrically insulating layer, and the first semiconductor region is separated from the first electrically-conductive element by the second electrically insulating layer;
a first doped semiconductor region within the second trench, the first doped semiconductor region is within the first semiconductor region, and the first doped semiconductor region has a second conductivity type opposite to the first conductivity type;
a second doped semiconductor region within the second trench, the second doped semiconductor region is within the first semiconductor region, the second doped semiconductor region has the first conductivity type, and the second doped semiconductor region is spaced apart from the first doped semiconductor region by a respective portion of the first semiconductor region between the first doped semiconductor region and the second doped semiconductor region;
a transistor having a gate contained in the first trench; and
wherein an electronic component, different from the transistor, at least partly defined by the first semiconductor region, the first doped semiconductor region, and the second doped semiconductor region, and the electronic component is at least partly contained within the second trench.
2 . The electronic device according to claim 1 , further comprising:
at least one third trench extending in the semiconductor substrate at least along a portion of the semiconductor substrate between the second trench and the first trench;
a second electrically-conductive element contained in the third trench; and
a third electrically-insulating layer between the second electrically-conductive element and the semiconductor substrate.
3 . The electronic device according to claim 2 , wherein the at least one third trench includes two third trenches extending in the semiconductor substrate on either side of the second trench.
4 . The electronic device according to claim 2 , wherein each third trench of the at least one third trench is totally separate from the second trench.
5 . The electronic device according to claim 2 , wherein each third trench meets at each end the second trench, the second electrically-conductive element being contiguous to the first electrically-conductive element.
6 . The electronic device according to claim 2 , further comprising:
a fourth trench extending in the semiconductor substrate and totally surrounding the second trench and the at least one third trench, the first trench being on a side of the fourth trench opposite to the second trench;
a third electrically-conductive element contained in the fourth trench; and
a fourth electrically-insulating layer between the third electrically-conductive element and the semiconductor substrate.
7 . The electronic device according to claim 6 , wherein the transistor comprises:
a fifth electrically-insulating layer between the gate of the transistor and the semiconductor substrate and forming a gate insulator of the transistor;
a fourth electrically-conductive element located in the first trench;
a sixth electrically-insulating layer between the fourth electrically-conductive element and the semiconductor substrate;
a seventh electrically-insulating layer between the fourth electrically-conductive element and the gate;
a second semiconductor region of the semiconductor substrate, delimited by the first trench containing the gate; and
a semiconductor well in contact with the second semiconductor region and the gate insulator, and having a channel of the transistor located therein.
8 . The electronic device according to claim 7 , wherein, in operation, the first electrically-conductive element and the second electrically-conductive element are configured to be electrically connected to a source of a reference potential, and the third electrically-conductive element is configured to be electrically connected to the fourth electrically-conductive element.
9 . The electronic device according to claim 1 , wherein the electronic component is a diode.
10 . The electronic device of claim 1 , wherein the second doped semiconductor region is more heavily doped than the first semiconductor region.
11 . An electronic device comprising:
a semiconductor substrate;
a first trench and a second trench in the semiconductor substrate, the first trench and the second trench parallel to one another;
a first transverse trench in the semiconductor substrate, the first transverse trench that extends from the first trench and the second trench;
a first electrically insulating layer in and partially filling the first trench, the second trench, and the first transverse trench;
a first electrically-conductive element in and partially filling the first trench, the second trench, and the first transverse trench, the first electrically-conductive element is separated from the semiconductor substrate by the first electrically insulating layer;
a second electrically insulating layer in the first trench, on the first electrically-conductive element, and partially filling the first trench;
a semiconductor region recessed into the first electrically-conductive element within the first trench, the semiconductor region is on the second electrically insulating layer, and the semiconductor region has a first conductivity type, the semiconductor region contacts the first electrically insulating layer and the second electrically insulating layer, and the semiconductor region is separated from the first electrically-conductive element by the second electrically insulating layer;
a first doped semiconductor region within the first trench, the first doped semiconductor region is within the semiconductor region, and the first doped semiconductor region has a second conductivity type opposite to the first conductivity type;
a second doped semiconductor region within the second trench, the second doped semiconductor region is within the semiconductor region, the second doped semiconductor region has the first conductivity type, and the second doped semiconductor region is spaced apart from the first doped semiconductor region by a respective portion of the first semiconductor region between the first doped semiconductor region and the second doped semiconductor region;
a transistor having a gate in a transistor trench; and
an electronic component, different from the transistor, at least partly defined by the semiconductor region, the first doped semiconductor region, and the second doped semiconductor region, and the electronic component at least partly contained within the first trench.
12 . The electronic device according to claim 11 , further comprising:
a third trench in the semiconductor substrate and totally surrounding the first trench, the second trench, and the first transverse trench.
13 . The electronic device of claim 11 , further comprising a second transverse trench parallel to the first transverse trench, the second transverse trench extends from the first trench to the second trench.
14 . The electronic device of claim 13 , wherein the first transverse trench and the second transverse trench are separated from each other by the first trench and the second trench.
15 . The electronic device of claim 11 , wherein the electronic component is a diode.
16 . An electronic device comprising:
a semiconductor substrate;
a first trench extending into the semiconductor substrate;
a pair of second trenches extending into the semiconductor substrate, the pair of second trenches are separated from each other by the first trench, the pair of second trenches are parallel with the first trench, and the first trench is between the pair of second trenches;
a pair of transverse trenches that are transverse to the first trench and the pair of second trenches, the pair of transverse trenches extend between respective ends of the first trench and the pair of second trenches, the pair of transverse trenches are separated from each other by the first trench and the pair of second trenches, and the first trench and the pair of second trenches are between the pair of transverse trenches;
a first electrically insulating layer in and partially filling the first trench, the pair of second trenches, and the pair of transverse trenches;
an electrically-conductive element in the first trench, the pair of second trenches, and the pair of transverse trenches, the electrically-conductive element is spaced apart from the semiconductor substrate by the first electrically insulating layer;
a second electrically insulating layer in the first trench, on the electrically-conductive element, and partially filling the first trench;
a first semiconductor region recessed into the electrically-conductive element within the first trench, the first semiconductor region is on the second electrically insulating layer, and the first semiconductor region has a first conductivity type, the first semiconductor region contacts the first electrically insulating layer and the second electrically insulating layer, and the first semiconductor region is separated from the electrically-conductive element by the second electrically insulating layer;
a first doped semiconductor region within the second trench, the first doped semiconductor region is within the first semiconductor region, and the first doped semiconductor region has a second conductivity type opposite to the first conductivity type;
a second doped semiconductor region within the second trench, the second doped semiconductor region is within the first semiconductor region, the second doped semiconductor region has the first conductivity type, and the second doped semiconductor region is spaced apart from the first doped semiconductor region by a respective portion of the first semiconductor region between the first doped semiconductor region and the second doped semiconductor region;
a transistor trench extending into the semiconductor substrate, the transistor trench is spaced apart from the pair of second trenches;
a gate of a transistor contained within the transistor trench; and
wherein an electronic component, different from the transistor, at least partly in the first trench and at least partly defined by the first semiconductor region, the first doped semiconductor region, and the second doped semiconductor region.
17 . The electronic device of claim 16 , further comprising a third trench extending into the semiconductor substrate, and the third trench is between a respective one of the pair of second trenches and the transistor trench.
18 . The electronic device of claim 17 , wherein the third trench surrounds the first trench, the pair of second trenches, and the pair of transverse trenches.
19 . The electronic device of claim 16 , wherein the pair of second trenches and the pair of transverse trenches surround the first trench.
20 . The electronic device of claim 16 , wherein the electronic component is a diode.