Can anyone offer me tips on spiral inductor design guideline? Is it advisable to use minimum width, minimum spacing? From Razavi's book it says that increasing spacing generally degrades the performance.
I will recommend analyzing the spiral inductors in HFSS. There is a good example on Ansoft website about Si spiral inductors. Best book to know about the effect of layout parameters on inductance , quality factor and self resonant frequency is "Integrated Passive Component Technology" by Richard K ulrich.
I began to design a spiral inductor recently ,and use a software called asitic,which i think you have known . Not only you can use it for design,but also can optimize your inductor with it,although it doesn`t have enough accurary.
Minimum spacing between turns is good for inductor and quality factor,but not minimum width.