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Building an extension for my mother-in-law

I love my mother-in-law but I never planned on living with her permanently. I have been enjoying her living with us now that we have kids but I feel like we all need some extra space so I am getting a granny flat built at the back of our block. This should allow us to have some extra space to make sure everyone has the privacy that they need whilst we can still be a family. This block has some tip on the process of building a granny flat including how to choose a contractor and how to get the council approval for the build.


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Building an extension for my mother-in-law

Understanding Trench Gates

by Chloe Cooper

Trench gates are dams that can be moved, raised and lowered if the water conditions are low. These trench gates were made of steel and wood for decades. The electric field in the general structure of the trench gates was focused only on the bottom, and long-term reliability was always an issue. However, in the structure of the double-trench that has been developed, the electric field is found in the source area too. This is to secure the concentration of the electric field and also to secure the long-term reliability of the trench gates.

Forming Trench Gates

Trench gates require a semiconductor layer at the bottom of the first conductivity, as well as on the upper semiconductor layer of the second conductivity. The purpose of this is to go against the first conductivity type that is on the bottom layer of the semiconductor.

There is a formation of at least one trench for the first gate and a second trench for the second gate. There is a gate insulator on the second trench gate which is filled with polysilicon. The second trench is a vertical extension of a depth that is deeper than the first trench.

At least one stacked layer will be formed on the upper section of the semiconductor layer so that at least one stacked layer has a floating body layer. This layer is the one that is on the second conductivity on a floating body layer that is on the first type of conductivity.

It will then form a region for the first conductivity type that goes on the stacked layer, where at least one stacked layer is found at the depth between the trench gate bottom and the bottom of the first trench.

Dummy Trench Gate

There are insulator gate bipolar transistor (IGBT) trench gates, which are dummies that go between two real trench gates. An emitting metal will be touching the dummy gate, so the emitter metal coverage will not be limited to between trenches only. The contact of the emitter metal has an area where it will be touching the dummy gate, which will enlarge the contact area of the emitter metal. It will accordingly lessen the distance between each real trench gates, and the dummy will no longer be affected by the emitter metal's minimum contact area anymore. In addition, the voltage drop turn-on of the trench gates will be reduced.

This information is important in understanding how trench gates work.