Richards powered home David Silva's second-half corner to settle a tense quarter-final with Reading at Eastlands on Sunday.
It earned City a trip to Wembley, where they will face rivals Manchester United on April 16 or 17, ending a three-decade wait for a last four appearance in the world's oldest domestic cup competition.
Living the dream: Richards was overwhelmed after his goal put Manchester City into the FA Cup semi-final
'It felt amazing,' the 22-year-old told the club's official website.
'To come through the youth academy and get us so far in the competition is an unbelievable feeling.
'We have United in the semis, which makes it more special. We can't wait.'
After failing to record a victory in two close encounters with United this season, Richards has already claimed there will be an element of revenge about the forthcoming encounter.
However, the England defender insists he did not know who City's opponents would be when the game started on Sunday, even though the draw had already been made.
'I didn't know but few of the boys did,' he said. 'It makes it more interesting. If we want to win the competition we have to beat the best.'
Head boy: Richards can't wait to take on rivals Manchester United at Wembley
Although beating United on such a stage would be an achievement to cherish, the main aim is to lift the trophy on May 14 and end that 35-year wait for silverware.
And if City do make it, the odds are Richards will have played a major part given his FA Cup history includes a last-gasp equaliser at Aston Villa during his debut season five years ago, and a stunning volley against Notts County in this season's competition prior to Sunday's match-winner.
'It is going well for me in this competition,' he said.
'I have always had a bit of a leap and I try to use it as much as I can so I am delighted with this goal.
'I have been working hard all season, practising the things I need to improve on, and it is paying off.
'I am playing with better players now. That helps you as well and I am enjoying every moment.'
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Source: Daily Mail
Source: Daily Mail