Semiconductor devices with low resistance gate and shield electrodes and methods

A semiconductor device, comprising:

• a region of semiconductor material comprising a first major surface and a first conductivity type;
• a trench gate structure comprising:
• an active trench extending from the first major surface into the region of semiconductor material;
• a shield dielectric layer adjacent to a lower portion of the active trench;
• a shield electrode adjacent to the shield dielectric layer, the shield electrode comprising a first polycrystalline semiconductor material;
• a gate dielectric layer adjacent to an upper portion of the active trench;
• a gate electrode adjacent to the gate dielectric layer in the upper portion of the active trench, the gate electrode comprising a second polycrystalline semiconductor material;
• a shield conductive layer adjacent to the shield electrode, the shield conductive layer comprising a first material, the first material comprising one or more of a metal material or a silicide material;
• a gate conductive layer adjacent to the gate electrode, the gate conductive layer comprising the first material;
• and
• a dielectric fill structure in the active trench electrically isolating the gate electrode and the gate conductive layer from the shield electrode and the shield conductive layer;
• a body region of a second conductivity type opposite to the first conductive type in the region of semiconductor material extending from the major surface adjacent to the trench gate structure;
• and
• a source region of the first conductivity type in the body region adjacent to the trench gate structure.

A method of forming a semiconductor device, comprising:

• providing a region of semiconductor material comprising a first major surface and a first conductivity type;
• providing a trench gate structure comprising:
• an active trench extending from the first major surface into the region of semiconductor material;
• a shield dielectric layer adjacent to a lower portion of the active trench;
• a shield electrode adjacent to the shield dielectric layer, the shield electrode comprising a first polycrystalline semiconductor material;
• a gate dielectric layer adjacent to an upper portion of the active trench;
• a gate electrode adjacent to the gate dielectric layer, the gate electrode comprising a second polycrystalline semiconductor material;
• a shield conductive layer adjacent to the shield electrode, the shield conductive layer comprising a first material, wherein the first material comprises one or more of a metal or a silicide;
• a gate conductive layer adjacent to the gate electrode, the gate conductive layer comprising the first material;
• and
• a dielectric fill structure in the active trench electrically isolating the gate electrode and the gate conductive layer from the shield electrode and the shield conductive layer;
• providing a body region of a second conductivity type opposite to the first conductive type in the region of semiconductor material extending from the major surface adjacent to the trench gate structure;
• and
• providing a source region of the first conductivity type in the body region adjacent to the trench gate structure.