Borosilicate Glass (BSG) as Gate Dielectric for 4H-SiC MOSFETs

2018 ◽  
Vol 924 ◽  
pp. 502-505 ◽  
Author(s):  
Yong Ju Zheng ◽  
Tamara Isaacs-Smith ◽  
Ayayi Claude Ahyi ◽  
S. Dhar

In this work, we investigate the effect of borosilicate glass (BSG) as gate dielectric on dielectric/4H-SiC interface traps and channel mobility in 4H-SiC MOSFETs. The interface trap characterization by C−ψs analysis and I-V characterization show lower fast interface trap density (Dit) as well as significant improvement of channel field-effect mobility on devices with BSG than that on devices with standard NO anneal. In addition, the results indicate interface trap density decreases with increasing B concentration at the interface of BSG/4H-SiC, which in turn, results in higher channel mobility.

2013 ◽  
Vol 740-742 ◽  
pp. 723-726 ◽  
Author(s):  
Narumasa Soejima ◽  
Taishi Kimura ◽  
Tsuyoshi Ishikawa ◽  
Takahide Sugiyama

We investigated the effects of the post-oxidation annealing (POA) atmosphere on the electrical properties and interfacial roughness of SiO2 deposited on a 4H-SiC (0001) face and SiC. POA in ammonia (NH3) gave MOS capacitors with a lower interface trap density and n-channel MOSFETs with higher field-effect mobility than POA in nitrous oxide (N2O) or nitrogen (N2). In contrast, POA in N2O gave a lower interface trap density than POA in N2, but it gave the lowest field-effect mobility of all the samples. Cross-sectional TEM observations revealed that N2O POA gave a higher interfacial roughness than NH3 POA. We thus considered that N2O POA degraded the inversion-layer mobility due to increased roughness scattering.


2014 ◽  
Vol 104 (13) ◽  
pp. 131605 ◽  
Author(s):  
Thenappan Chidambaram ◽  
Dmitry Veksler ◽  
Shailesh Madisetti ◽  
Andrew Greene ◽  
Michael Yakimov ◽  
...  

2006 ◽  
Vol 527-529 ◽  
pp. 1063-1066 ◽  
Author(s):  
Ayayi Claude Ahyi ◽  
S.R. Wang ◽  
John R. Williams

The effects of gamma radiation on field effect mobility and threshold voltage have been studied for lateral n-channel 4H-SiC MOSFETs passivated with nitric oxide. MOS capacitors (n and p) and n-channel lateral MOSFETs were irradiated unbiased (floating contacts) for a total gamma dose of 6.8Mrad (Si). The MOS capacitors were used to study the radiation-induced interface traps and fixed oxide charge that affect the performance of the MOSFETs. Radiationinduced interface traps were observed near the SiC valence band edge and just above mid-gap, and field effect channel mobility was reduced by 18-20% following irradiation. Even so, 4HMOSFETs appear to be more radiation tolerant than Si devices.


2017 ◽  
Vol 897 ◽  
pp. 115-118
Author(s):  
Martin Domeij ◽  
Jimmy Franchi ◽  
Krister Gumaelius ◽  
K. Lee ◽  
Fredrik Allerstam

Lateral implanted SiC MOSFETs and NMOS capacitors were fabricated and used to extract channel mobility and interface state density DIT for three different gate oxides. DIT values were extracted using the high(1 MHz)-low(1 kHz) method for NMOS capacitors and the subthreshold slope for MOSFETs. The subthreshold slope extraction gave 6-20 times higher DIT values compared to the high-low method, presumably because the high-low method cannot capture the fastest traps [1]. None of the methods resulted in clear proportionality between the inverse channel mobility and DIT. The subthreshold slope gave similar DIT values for samples with different surface p-doping concentrations indicating that the method is not sensitive to the threshold voltage.


2003 ◽  
Vol 801 ◽  
Author(s):  
Erik F. McCullen ◽  
Haripriya E. Prakasam ◽  
Wenjun Mo ◽  
Jagdish Thakur ◽  
Ratna Naik ◽  
...  

ABSTRACTWe have extended our previous investigation of the electrical characteristics of a Pd/AlN/Si thin film sensor for varying thicknesses of AlN, from 300–2000Å. The capacitance vs. voltage, C(V), and conductance vs. voltage, G(V), measurements were utilized to investigate the presence of surface states within the Si gap at the AlN/Si interface. Our previous experiments on 500Å AlN did show the presence of interface traps, with an estimated surface density between 8×1014 and 1.5×1015 m−2eV−1 [1]. In our present work we've examined the effect of AlN thickness on the density of these interface traps. The density is dependent on AlN thickness. The thinner devices, 300Å, showed an interface trap density of 20–30×1015 m−2eV−1. The interface trap density decreased with increasing thickness up to 500Å, where the density remained relatively constant at about 1–5×1015 m−2eV−1 for thicknesses up to 2000Å. We have also shown that the interface trap density is independent of annealing.


RSC Advances ◽  
2020 ◽  
Vol 10 (17) ◽  
pp. 9902-9906 ◽  
Author(s):  
Kuan-Yu Chen ◽  
Chih-Chiang Yang ◽  
Chun-Yuan Huang ◽  
Yan-Kuin Su

The amorphous indium gallium oxide thin film transistor was fabricated using a cosputtering method.


2014 ◽  
Vol 806 ◽  
pp. 139-142 ◽  
Author(s):  
Yogesh K. Sharma ◽  
A.C. Ahyi ◽  
Tamara Issacs-Smith ◽  
M.R. Jennings ◽  
S.M. Thomas ◽  
...  

The NO (nitric oxide) passivation process for 4H-SiC MOSFETs (silicon carbide metal-oxide-semiconductor filed effect transistors) effectively reduces the interface trap density and increases the inversion channel mobility from less that 10 to around 35cm2/V.s, only 5% of the bulk mobility. Recent results on the phosphorous passivation of the SiO2/4H-SiC interface have shown that it improves the mobility to about 90 cm2/V.s. Phosphorous passivation converts oxide (SiO2) into phosphosilicate glass (PSG) which is a polar material and results in device instabilities under abias-temperature stress (BTS) measurements. To limit the polarization effect, a new thin PSG process has been developed. The interface trap density of 4H-SiC-MOS capacitors using this process is as low as 3x1011cm-2eV-1. BTS results on MOSFETs have shown that the thin PSG devices are as stable as NO passivated devices with mobility around 80 cm2/V.s.


Sign in / Sign up

Export Citation Format

Share Document