That's almost certainly going to count as a booby trap, so yes, that's illegal.

There are devices made to deter traffic from driving on your lawn without inflicting damage. 

It’s not always the same driver either. So you’re just going to continuously damage Amazon trucks and disable them in your front yard. I’d go with a device that is visible and does not cause damage. 

Amazon can refuse to deliver to your house once they pick up on it.

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This is an incredibly bad idea. If they're driving on your yard, just put a decorative fence or yard stones up. If a child runs onto the yard and imbeds a caltrop in your feet, you'll likely be facing criminal charges.

Will putting caltrops in my yard get me in trouble?