Learning Forum

[prathamesh.bhide04]

Greetings,
I am simulating the inductance for a 2.5 circular spiral inductor fabricated on a glass-substrate fabricated in my lab.
The dimensions are in millimeters, and the inductance measurement was done using a Keysight E4980A LCR Meter.

A screenshot of the design is attached.

I have checked that the model matches with the fabricated piece. Although, the fabricated piece does not have a ground ring. But in my previous simulation to validate my simulation environment, I was able to replicate an existent paper's Inductance and Q Factor values using the Y parameters (although it used VNA measurements instead of LCR meter measurements and the fabrication included a ground ring).
I used the formulae: L = im(1/Y11)/(2*pi*freq) and Q = -im(Y11)/re(Y11). There is also a region defined for the airbox.

When I simulate this setup, I am getting an inductance of around 60 nH at 300 KHz of frequency. However, the measured value is 360 nH at 300 KHz.

I am getting similar inductance values (~60 nH) when simulating the same using ANSYS Maxwell and Q3D. Another issue of concern is that the measured DC resistance is 1 ohm, whereas the Q3D simulation is around 0.6 ohms.

1. Will VNA and LCR meter measurements require different excitations in HFSS? My previous validated simulation was from a VNA measurement unlike this one which uses an LCR meter.

2. If there is no ground ring in the fabricated piece, is this ground ring approach still correct to get the measured values?

3. Is there anything in particular that could be causing such a drastic difference between simulated and measured values?

Thank you for your time and consideration!