Basic transistor switch
I would think that your circuit would produce around 5V or more at the emitter of the NPN transistor, so I am thinking there is something not quite right somewhere. However your circuit will never work the way you want it to, so I am hesitant to spend too much time thinking about it.

Here is one circuit that will work the way you want. Just apply your 6V control signal to 9V_ENABLE. VCC_9V_SWITCHED will be 9V when 9V_ENABLE is high. You don't say how much current you are expecting. So I am not sure if the BSS84 is really a good choice. If you add a current requirement on the 9V supply, someone might be able to select a better choice for M1.

Good luck and keep at it!







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