a process for manufacturing a multi - layer glass ceramic substrate which includes the steps of forming green sheets containing ceramic powders and glass powders as main ingredients , laminating the green sheets , and firing the laminated green sheets to form a multi - layer glass ceramic substrate , wherein at least one green sheet containing porous glass powders as a part of the glass powders , is provided to control the shrinkage of the green sheets and prevent cracks or delamination . the preferred process includes the steps of forming a single layer by i ) forming first green sheets containing ceramic powders , glass powders , hollow glass spheres and porous glass powders as main ingredients , ii ) forming an interconnection layer on each of the first green sheets , and iii ) laminating the first green sheets with the interconnection layer ; sandwiching the signal layer between upper and lower green sheets containing ceramic powders and glass powders as main ingredients ; and firing the sandwiched signal layer to form the multi - layer glass ceramic substrate .