I'm not familiar with a Mod 700 semi-auto. But that doesn't mean there isn't one. Marlin has made millions of semi-auto .22's and many had specific model numbers depending upon the wishes of a particular company and/or distributor. It is possible you have a retailer version of the Model 60.
Perhaps you could provide some specific details such as: label information, barrel length, cartridge capacity, tube feed or clip, stock shape and if there is any designs in the stock, metal finish, etc.
In the meantime ... here a a few potential models:
Model 70: Carbine version of the Model 60 rifle made in different variations under both the Glenfield moniker as well as the Marlin label.
Model 7000: A heavy bull barrel carbine version of the Model 60. Semi-auto, clip feed.
Model 7000T: A target stocked version of the Mod 7000.
There was also a Model 700 series of bolt action .22's/.22 mag's. i.e.; 780, 781, 782, 783.
