Title :
Picosecond photoconductivity using a graded bandgap Al/sub x/Ga/sub 1-x/As active detecting layer
Author :
Morse, J.D. ; Mariella, R.P. ; Dutton, R.W.
Author_Institution :
Lawrence Livermore Nat. Lab., CA, USA
Abstract :
Improved responsivity for picosecond photoconductors is achieved by utilizing a graded bandgap Al/sub x/Ga/sub 1-x/As active detecting layer grown on a high-defect-density, low-temperature GaAs layer by MBE (molecular beam epitaxy). By taking advantage of the superior transport properties of the graded Al/sub x/Ga/sub 1-x/As layer, order-of-magnitude improvement in responsivity has been demonstrated, along with 2-6 times improvement in peak photocurrent response. This provides a capability to design photodetector speeds into the <10-ps regime.<>
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; molecular beam epitaxial growth; photoconducting devices; 10 ps; Al/sub x/Ga/sub 1-x/As active detecting layer; Al/sub x/Ga/sub 1-x/As-GaAs; GaAs substrate; MBE; graded bandgap; low-temperature GaAs layer; molecular beam epitaxy; peak photocurrent response; picosecond photoconductivity; responsivity; transport properties; Charge carrier processes; Crystalline materials; Gallium arsenide; Lattices; Molecular beam epitaxial growth; Photoconducting materials; Photoconductivity; Photodetectors; Photonic band gap; Temperature;
Conference_Titel :
Electron Devices Meeting, 1989. IEDM '89. Technical Digest., International
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-0817-4
DOI :
10.1109/IEDM.1989.74156
