**5. Conclusion**

**Figure 17.** Structures used for extracting the equivalent capacitances of InP / In0.53Ga0.47As HPT based SG-OEMs. The

**Figure 18.** Total device capacitance and capacitance of a single reverse-biased base-emitter/ collect junction of InP /

A set of AC simulations were carried out on the two structures displayed in Figure 17, with NA = 2.5x1016 cm-3 and ND = 5x1015 cm-3. The simulations were carried out for dark conditions and the DC bias voltage was swept from 0 to 5V, with a small signal perturbation applied to the bias

full SG-OEM structure is on the left, and a single base-emitter junction is on the right.

110 Optoelectronics - Advanced Materials and Devices

In0.53Ga0.47As HPT based SG-OEMs.

Symmetric gain optoelectronic mixers based on InP/ In0.53Ga0.47As heterostructures are promising candidates use in the receivers of chirped-AM LADAR systems. These devices can reduce LADAR system component count and complexity, and improve their perform‐ ance. Two dimensional device simulations were used to optimize device structure parame‐ ters, including base width and doping density, and emitter/collectorlayer doping density. It was determined that highly doped interface layers caused an increase in dark current and device capacitance and also lowered the base punch through breakdown voltage. Therefore, the optimized device design does not contain such an interface layer.
