I have a simple switch circuit that is powered with a single 1.5V alkaline battery. I want to find a MOSFET(or other device) that will switch on when the battery voltage is applied. I can find plenty of FETs with a Vgs of 1.5V but none that seem to switch on properly if the battery is a bit flat (ie 1V).

So I'm after Vgs of less than 1V, drain current is less than 100mA, Vds is the battery voltage, ie 1 to 1.5V.

Any ideas?