Quantum computers are becoming more and more relevant in today's world to compete with traditional computing solutions. To achieve such performance levels it is necessary to integrate the bulky control, bias, and readout electronics inside the dilution fridge to scale the number of qubits inside the quantum computer. Low noise amplifiers realized with InAlAs and InGaAs HEMTs are a viable option to transfer the readout amplification to the 4K stage. Self-heating of these devices in this operating condition is not fully characterized yet and this work wants to understand how this affects the area around the HEMT to evaluate future on-wafer integration.