Transistor die with output bondpad at the input side of the die, and power amplifiers including such dies

A field effect transistor comprising:

• a semiconductor die with an input die side and an opposed output die side, wherein the semiconductor die includes a base semiconductor substrate and a build-up structure over a top surface of the base semiconductor substrate;
• a first transistor finger integrally formed in the semiconductor die between the input die side and the output die side, wherein the first transistor finger includes
• a first gate extending in a first direction from the input die side toward the output die side and overlying a first channel region in the base semiconductor substrate, wherein the first gate has a first gate end proximate to the input die side, a second gate end proximate to the output die side, and first and second gate sides extending between the first and second gate ends,
• a first drain region in the base semiconductor substrate and extending in the first direction, wherein the first drain region is located adjacent to the first gate side, and
• a first drain contact overlying the first drain region and extending in the first direction, wherein the first drain contact has a first drain contact end proximate to the input die side, and a second drain contact end proximate to the output die side;
• a first gate bondpad electrically connected to the first gate, wherein the first gate bondpad is integrally formed in the build-up structure between the input die side and the first transistor finger;
• and
• a first input-side drain bondpad directly electrically connected to the first drain contact, wherein the first input-side drain bondpad is integrally formed in the build-up structure between the input die side and the first transistor finger.

A power amplifier comprising:

• an amplifier substrate;
• an amplifier input coupled to the amplifier substrate;
• an amplifier output coupled to the amplifier substrate;
• a transistor die coupled to the amplifier substrate, wherein the transistor die includes
• a semiconductor die with an input die side and an opposed output die side,
• a transistor integrally formed in the semiconductor die between the input die side and the output die side, wherein the transistor has an input and an output,
• an input bondpad integrally formed in the semiconductor die between the input die side and the transistor, wherein the input bondpad is electrically connected to the input of the transistor,
• a first output bondpad integrally formed in the semiconductor die between the input die side and the transistor, and
• a conductive structure integrally formed in the semiconductor die that directly electrically connects the output of the transistor to the first output bondpad;
• and
• an output circuit electrically coupled between the transistor and the amplifier output, wherein the output circuit includes at least one first bondwire coupled to the first output bondpad.