Resistor $R_{1}$ in the circuit below has been adjusted so that $I_{1}=1$ $mA$. The bipolar transistors $Q1$ and $Q2$ are perfectly matched and have very high current gain, so their base currents are negligible. The supply voltage $V_{cc}$ is $6$ $V$. The thermal voltage $KT/q$ is $26$ $mV$.
The value of $R_{2}$ (in $\Omega)$ for which $I_{2}=100\mu A$ is _________