Dear friends,
I have a sample as below
..
Undoped GaAs caplayer, 17 quantum wells (with AlGaAs and  GaAs), undoped AlAs,
Highly doped GaAs, and the undoped GaAs substrate.
I wish to deplete the quantum wells by applying a gate voltage. I am not able to
deplete all the quantum wells. Now I have just included the highly doped GaAs
layer, with an intension of making the layer as a back gate.
I am using Ni/AuGe/Ni/Au for the ohmic contact and Cr/Au for the gate.Also I
would like to know about the combination for a lateral ohmic contact, to etch
deep and then to make the ohmic contact-but without penetration to the highly
doped GaAs layer, which I have to make as a back gate.
If u have some idea, pls help me

..
Aji


Aji A. Anappara
Thriveni, Chittar
Anappara, Trivandrum
India-695551.