This　paper　presents　an　automated　digital　image　correlation　(DIC)　system　for　in-plane　micro-deformation　analysis.　The　system　features　microscale　resolution,　realtime　thermal　ramp　and　cycling　loading,　image　auto-positioning　and　autofocus　for　image　acquisition,　and　novel　element-based　DIC　algorithm.　The　DIC　tool　is　demonstrated　to　a　micro-deformation　measurement　application　of　a　solder　joint　in　a　plastic　Ball　Grid　Array　(BGA)　package.　The　solder　joint　deformation　has　been　investigated　under　two　loading　cases,　temperature　ramp　and　temperature　cycling.　Finite　element　analyis　was　conducted　and　the　U　and　V　displacemnts,　and　calculated　strain　distribution　in　the　solder　joint　is　compared　with　the　DIC　measured　result.　The　measured　and　predicted　displacement　fields　under　temperature　ramp　give　good　agreement.　Research　on　nano-scale　DIC　measurements　must　employ　an　atomic　force　microscope　(AFM)　for　in-situ　digital　imaging　of　in-plane　deformation.　It　was　discovered　through　calibration　that　AFM　scanner　drift　is　a　intrinsic　error　and　thus　a　correction　methodology　is　required　for　DIC　application.　The　application　the　AFM/DIC　technique　is　used　for　deformation　characterization　of　solder　interconnection　in　a　micro-thermoelectric　cooler　system　subject　to　a　small　temperature　gradient　of　+25C　to　-25C.　©　2006　IEEE.