Insulating glass units with low-E and antireflective coatings, and/or methods of making the same

An insulating glass (IG) unit, comprising:

• first, second, and third substantially parallel spaced apart glass substrates, the first substrate being an outermost substrate and the third substrate being an innermost substrate;
• a first spacer system disposed around peripheral edges of the first and second substrates, a first cavity being defined between the first and second substrates;
• a second spacer system disposed around peripheral edges of the second and third substrates, a second cavity being defined between the second and third substrates;
• first and second low-emissivity (low-E) coatings disposed on interior surfaces of the first and third substrates respectively such that the first and second low-E coatings face one another;
• first and second antireflective coatings disposed on opposing major surfaces of the second substrate,
• wherein each said low-E coating comprises, in order moving away from the substrate on which it is disposed:
• a layer comprising titanium oxide,
• a layer comprising zinc oxide,
• an infrared reflecting layer comprising silver,
• a layer comprising a metal, oxide, or sub-oxide of Ni and/or Cr,
• a layer comprising tin oxide, and
• a layer comprising silicon nitride, and
• wherein the IG unit has a visible transmission of at least about 70%, a U-value of less than or equal to about 0.80, and a g-value of at least about 60;
• and
• wherein each of the low-E coatings is heat treatable and has a ΔE* value of less than 2.5.