Do an interferogram and include coherence
Apply goldstein filtering to clean it up or multilook it (uncheck output
intensity)
Don’t apply topo phase removal if you want a DEM.
Export to Snaphu Select TOPO mode for DEM generation and method MCF
From Linux, run snaphu with the command in the snaphu.conf file
Import from snaphu into SNAP
Run Dem Generation
http://step.esa.int/main/doc/tutorials/sentinel-1-toolbox-tutorials/