Multiple subthreshold swing circuit and application to displays and sensors

An apparatus, comprising:

• a transistor including a gate, a first terminal, and a second terminal;
• and
• a set of one or more serially-connected diodes, each diode having a first terminal and a second terminal, wherein the first terminal of a first diode in the set of one or more serially-connected diodes is connected to the second terminal of the transistor, wherein at least one diode in the set of one or more serially-connected diodes comprises:
• a first layer including silicon having a first type of carrier as its majority carrier;
• the first terminal of the at least one diode including a second layer formed on the first layer, the second layer comprising intrinsic amorphous hydrogenated silicon, a third layer formed on the second layer, the third layer comprising amorphous hydrogenated silicon having a second type of carrier as its majority carrier, and a first conductive layer formed on the third layer;
• and
• the second terminal of the at least one diode comprising a fourth layer formed on the first layer, the fourth layer comprising crystalline hydrogenated silicon having the first type of carrier as its majority carrier, and a second conductive layer formed on the fourth layer;
• wherein the gate of the transistor is not directly connected with the set of one or more serially-connected diodes.