Schottky diode for bipolar LSI's consisting of an impurity-controlled Si substrate and Al(2%Si) electrode

Circuit design conditions of Schottky diodes have been investigated and the fabrication method for diodes suitable for the conditions has been proposed for applications to bipolar LSI's, such as ECL RAM and Schottky TTL. It has been found that the desired Schottky diode for bipolar LSI's is not an ideal device from the theoretical point of view. Desired built-in voltage, ideal factor, series resistance, and junction capacitance for the Schottky diode have been estimated, respectively, for the bipolar RAM and Schottky TTL. A proposed Schottky diode consists of an impurity-concentration-controlled (111) Si substrate by arsenic-ion implantation and an aluminum with 2-percent silicon electrode: Al(2%Si). The fabrication method of the diode, along with its thermal stability and reproducibility, have also been investigated from the view point of stable VLSI fabrication process establishments. Utilizing this Schottky diode, a very high-speed bipolar RAM [l], [2], [7] and a large-scale Schottky TTL VLSI [3] have been fabricated and their high-speed performance and high yield have been verified.