Abstract

The concept of a “separate absorption and multiplication” region avalanche photodiode⁽¹⁾ (SAM-APD) has been extended out past 2 μm by using the In_0.7Ga_0.3As/lnAs_0.3P_0.7 system. Figure 1 contains a sketch of the structure which utilizes no compositional grading. Although the two materials are lattice-matched to each other, there is nearly 1% mismatch with the P+lnP substrate. The use of a heavily doped p-type substrate, along with the 100 μm diameter mesa structure beveled as shown, causes the depletion region to “bend away” at the edges and thus eliminates edge breakdown.

© 1995 Optical Society of America