Low- and high-resistivity silicon substrate characterization using the Al/silicon-rich oxide/Si structure with comparison to the metal oxide semiconductor technique

Abstract

High-resistivity silicon substrates (HRS, NB<1014cm−3) are commonly used, especially in optoelectronic integrated circuits. However, standard metal oxide semiconductor (MOS) characterization methods fail to predict correctly the dopant concentration and lifetime. This is due to the high resistance in series with the MOS capacitor, which causes an erroneous capacitance measurement at high frequency. To overcome this restriction, a different characterization method is proposed, using the electronic transport property of silicon-rich oxide (SRO) films, with aluminum/silicon-rich oxide (Al/SRO/Si) devices and using capacitance-voltage (C-V) and current-voltage (I-V) characteristics, the dopant concentration and lifetime can be estimated with these method. In addition, using low/high-frequency C-V measurements in MOS structure on HRS can be used to determine the dopant concentration. In this work, low-resistivity silicon and HRS substrates are characterized. The results for both type of substrates and for the different methods are compared. It is shown that the results are similar and any of these methods produce reliable results, but the Al/SRO/Si structure has the advantage that the generation lifetime is easily obtained.

UV-Vis Photodetector with Silicon Nanoparticles

“…Härkönen et al (Härkönen et al, 2006) studied the lifetime of high resistivity silicon under low and high injection levels of carriers. They found that for high resistivity silicon the recombination lifetime is longer than 1 ms. Just for reference in our group, generation lifetime of high resistivity silicon was estimated to be between 1 and 2 ms (Luna et al, 2005). Then, a value of diffusion of 0.114 cm, or 1140 m is calculated.…”