The invention discloses a metallization and 
heat sink integrated preparation method of an AlN 
ceramic substrate. According to the preparation method, a Ti metallization layer, a Ti-Cu gradient 
transition layer and a Cu 
heat sink layer are sequentially formed on the AlN 
ceramic substrate by the aid of a 
physical vapor deposition technology, and a 
transition layer Al3Ti+
TiN is formed between an AlN layer and a Ti layer in the 
deposition process. The method specifically comprises the steps that surface 
polishing treatment is performed on the AlN 
ceramic substrate; the polished AlN 
ceramic substrate is soaked, cleaned and then dried; the surface of the cleaned AlN 
ceramic substrate is sequentially plated with the Ti metallization layer, the Ti-Cu gradient 
transition layer and the Cu 
heat sink layer by the aid of a magnetron 
sputtering deposition method, in the 
deposition process, the transition layer Al3Ti+
TiN is automatically formed between the AlN layer and the Ti layer, and finally, the metallization and heat sink integrated AlN 
ceramic substrate is formed. According to the method, the metallization and heat sink integrated plating layer is deposited on the AlN ceramic substrate by the aid of the high vacuum magnetron 
sputtering technology, so that the overall packaging strength is greatly improved, the packaging process flow is shortened, the packaging consumption is reduced, and the production cost is remarkably reduced.