Understanding Microstrip Tee

Questions:

1) Purpose of microstrip Tee
2) how do microstrip Tees work?

3) When to use microstrip Tee?
For example, in the attachment shown...is it right to use a Tee here. I mean, I've to connect two microstrip lines and one diode. Should I use tee or something else?

Any help will be appreciated.

Yes, U use a MTee when ever there is a change in a single line to double line split, That it may take into account for the additional capacitance effects that get added at the junction of the line division,.. U can use it the way u have connected it in the pic,.. In general it is expected to use MLine first to increase a little length before connecting any other component like diode in ur case.