Radio frequency device and radio frequency front-end apparatus

A radio frequency device, comprising:

• a substrate;
• an epitaxial structure including a buffer layer, a channel layer, and a barrier layer that are disposed on said substrate in such order;
• a first electrode formed on said epitaxial structure and including a first electrode body and a plurality of parallel, spaced-apart first electrode fingers each extending in a first direction and connected to said first electrode body;
• a second electrode formed on said epitaxial structure, and including a second electrode body and a plurality of parallel, spaced-apart second electrode fingers each extending in the first direction and connected to said second electrode body, said first electrode body and said second electrode body being oppositely arranged in the first direction, said first electrode fingers and said second electrode fingers being interdigitated between said first electrode body and said second electrode body to form a serpentine channel therebetween;
• a gate structure including a first sub-gate that is formed on said epitaxial structure, that is disposed between said first electrode and said second electrode, and that has multiple first parallel portions each extending in the first direction and multiple first vertical portions each extending in a second direction perpendicular to the first direction, said first parallel portions and said first vertical portions being alternately connected to one another in series to form a serpentine shape and extending in said serpentine channel;
• a first metal bulk formed on said epitaxial structure;
• a first auxiliary metal bulk formed on said epitaxial structure;
• and
• a first metal connection line electrically connecting said first metal bulk to said second electrode body and electrically insulated from said first sub-gate;
• said first auxiliary metal bulk and said first metal bulk being arranged between corresponding adjacent two of said first parallel portions of said first sub-gate and between a corresponding one of said first vertical portions that interconnects the corresponding adjacent two of said first parallel portions and an end of a corresponding one of said first electrode fingers that is surrounded by the corresponding adjacent two of said first parallel portions and the corresponding one of first vertical portions, the end of the corresponding one of said first electrode fingers being distal from said first electrode body,
• said first metal bulk being positioned between said first auxiliary metal bulk and the corresponding one of said first vertical portions,
• one of said first electrode and said second electrode serving as a drain electrode and the other as a source electrode.