Organic‐on‐inorganic semiconductor contact barrier devices

The organic compound 3,4,9,10‐perylenetetracarboxylic dianhydride (PTCDA) has previously been observed to undergo a large increase in conductivity on irradiation with energetic particle beams. In this letter, we describe the electrical characteristics of novel rectifying junctions employing unirradiated PTCDA vapor deposited onto 10‐Ω cm p‐Si substrates. The PTCDA‐Si contact barrier has a height of φB = 0.74 eV. The resulting diodes undergo avalanche breakdown at VB = 230 V, and exhibit current densities at 1/2  VB of ⩽50  μA/cm2. In addition, the forward current‐voltage (IF−V) characteristics are strongly dependent on the contact metal used on the top PTCDA surface. The best results obtained were for diodes employing Ti contacts which gave nonhysteretic, stable IF‐V characteristics with an ideality factor of n = 1.7. Several properties of the as‐deposited PTCDA are also discussed. The rectifying characteristics reported here, coupled with the properties of irradiated PTCDA, suggest many unique device applications.The organic compound 3,4,9,10‐perylenetetracarboxylic dianhydride (PTCDA) has previously been observed to undergo a large increase in conductivity on irradiation with energetic particle beams. In this letter, we describe the electrical characteristics of novel rectifying junctions employing unirradiated PTCDA vapor deposited onto 10‐Ω cm p‐Si substrates. The PTCDA‐Si contact barrier has a height of φB = 0.74 eV. The resulting diodes undergo avalanche breakdown at VB = 230 V, and exhibit current densities at 1/2  VB of ⩽50  μA/cm2. In addition, the forward current‐voltage (IF−V) characteristics are strongly dependent on the contact metal used on the top PTCDA surface. The best results obtained were for diodes employing Ti contacts which gave nonhysteretic, stable IF‐V characteristics with an ideality factor of n = 1.7. Several properties of the as‐deposited PTCDA are also discussed. The rectifying characteristics reported here, coupled with the properties of irradiated PTCDA, suggest many unique device app...