Broadband power transistor devices and amplifiers and methods of manufacture thereof

A packaged radio frequency (RF) amplifier device comprising:

• a device substrate;
• a first input lead coupled to the device substrate;
• a first output lead coupled to the device substrate;
• a first transistor die coupled to the device substrate, wherein the first transistor die includes a first transistor, a transistor input terminal coupled to the first input lead, and a transistor output terminal coupled to the first output lead, and wherein the first transistor has a drain-source capacitance below 0.2 picofarads per watt;
• a first integrated passive device coupled to the device substrate;
• and
• an impedance matching circuit coupled between the transistor output terminal and the first output lead, wherein the impedance matching circuit includes
• a harmonic termination circuit comprising a first inductive element and a first capacitance connected in series between the transistor output terminal and a ground reference node, wherein an equivalent capacitance from a combination of the first inductive element and the first capacitance in series effectively increases the drain-source capacitance by at least 10 percent, the first inductive element includes a first plurality of bondwires with first ends connected to the first transistor die and second ends connected to the first integrated passive device, and the harmonic termination circuit resonates at a harmonic frequency of a fundamental frequency of operation of the RF amplifier device, and
• a second inductive element and a second capacitance connected in series between the transistor output terminal and the ground reference node, wherein the second inductive element includes a second plurality of bondwires with first ends connected to the output terminal of the transistor die and second ends connected to the first integrated passive device, and wherein the second plurality of bondwires and the second capacitance are directly connected.

A method of manufacturing a radio frequency (RF) amplifier device, the method comprising the steps of:

• coupling an input lead to a device substrate;
• coupling an output lead to the device substrate;
• coupling a transistor die to the device substrate between the input and output leads, wherein the transistor die includes a transistor and a transistor output terminal, and wherein the transistor has a drain-source capacitance below 0.2 picofarads per watt;
• coupling an integrated passive device to the device substrate between the transistor die and the output lead, wherein the integrated passive device includes a first capacitance and a second capacitance, wherein the first capacitance includes one or more first capacitors that are integrally formed with the integrated passive device, and the second capacitance also is integrally formed with the integrated passive device;
• creating a harmonic termination circuit by connecting a first inductive element in the form of a first plurality of bondwires between the transistor output terminal and the first capacitance, wherein first ends of the first plurality of bondwires are connected to the transistor output terminal, and second ends of the first plurality of bondwires are connected to a first bond pad on the integrated passive device that is coupled to the first capacitance, and wherein an equivalent capacitance from a combination of the first inductive element and the first capacitance in series effectively increases the drain-source capacitance by at least 10 percent, and the harmonic termination circuit resonates at a harmonic frequency of a fundamental frequency of operation of the RF amplifier device;
• and
• creating a portion of an impedance matching circuit by connecting a second inductive element in the form of a second plurality of bondwires between the transistor output terminal and the second capacitance, wherein first ends of the second plurality of bondwires are connected to the transistor output terminal, and second ends of the second plurality of bondwires are connected to a second bond pad on the integrated passive device that is coupled to the second capacitance, and wherein the second plurality of bondwires and the second capacitance are directly connected.