Novel Low-Temperature Polycrystalline-Silicon Power Devices with Very-Low On-Resistance Using Excimer Laser-Crystallization

Abstract

Low-temperature poly-Si lateral double-diffused metal oxide semiconductor ͑LTPS LDMOS͒ with high voltage and very low on-resistance has been achieved using excimer laser crystallization at 400°C substrate heating for the first time. The ON/OFF current ratios were 2.96 ϫ 10 5 and 6.72 ϫ 10 6 while operating at V ds ϭ 0.1 and 10 V, respectively. The maximum current limit was up to 10 mA and maximum power limit could be enhanced over 1 W at V ds ϭ 90 V and V gs ϭ 20 V. The R on,sp with dimensions of W/L ch ϭ 600 m/12 m could be significantly decreased 6.67 ϫ 10 2 times in magnitude as compared with conventional offset drain thin-film-transistors.

MgZnO High Voltage Thin Film Transistors on Glass for Inverters in Building Integrated Photovoltaics

“…In the case of poly-Si HVTFTs, Cheng et al . 15 demonstrated poly-Si lateral double diffused metal oxide semi-conductor (LDMOS). The blocking voltage reached 240V, and on/off ratio was ~10 6 .…”

Fabrication of Novel Three-Step Drift-Doped Low-Temperature Polycrystalline Silicon Lateral Double-Diffusion Metal–Oxide–Semiconductor Using Excimer Laser Crystallization

“…It was found that a large grain size could be realized by controlling the solidification of silicon under these conditions. 19,20) Figure 2 shows a scanning electron microscopy (SEM) image of poly-Si.…”

“…It was found that a large grain size could be realized by controlling the solidification of silicon under these conditions. 19,20) Figure 2 shows a scanning electron microscopy (SEM) image of poly-Si. Step 5: deposit a 3000-A ˚-thick layer of tetraethylorthosilicate (TEOS) as the field oxide (FOX) by LPCVD.…”

“…[20][21][22][23] If the process and excimer laser systems exhibit optimal conditions, the specific on-resistance of uniformly doped LTPS LDMOS may be reduced to about 0.54 cm 2 , which is only five times higher than that of single-crystalline silicon LDMOS, with the same order of block capability. 19) In this study, uniformly doped and three-step-doped LTPS LDMOSs were manufactured by the same process within the same time. The performance of specific on-resistance is lower than that reported in our previous paper.…”

“…ECL is the most promising technique for growing large poly-Si grains and it cannot cause damage to the glass substrate because of a large absorption coefficient for a-Si in the UV light region (optical absorption coefficient > 10 6 cm À1 ). [16][17][18][19] The grain boundary causes many defects, which act as trap states in the band gap and degrade the electrical characteristics of devices, such as threshold voltage, mobility, and subthreshold swing. In this work, we focused on the study of LTPS-LDMOSFETs and compared LDMOS with LIGBT.…”