Test piece preparation method suitable for chip stack packaging substrate thickness local thinning

The invention provides a method for preparing a test piece suitable for locally thinning the thickness of a substrate in chip stack packaging. The method comprises the following steps of: providing an advanced test piece in chip stack packaging; determining the position of a point to be analyzed in the test piece; a laser instrument is arranged above the test piece, and the laser instrument is used for carrying out laser thinning on the test piece until the thickness of the test piece reaches a preset thickness; according to the method, the thinned test piece is subjected to test piece analysis and detection by using an analysis tool, whether the thinned thickness can support analysis of the test piece or not is judged, the test piece is thinned in a laser mode, the situation of damage caused by manual grinding is avoided, the grinding success rate of the test piece is increased, and the test piece analysis cost is reduced. 本发明提供一种适用于芯片堆栈封装局部减薄基板厚度的试片制备方法，该方法包括以下步骤：提供一先进芯片堆栈封装的试片；确定所述试片内的欲分析点位置；所述试片上方设置有镭射仪，所