GRINDING METHOD OF WORKPIECE

To prevent formation of scratch for the reverse face or occurrence of crack in a workpiece due to entrainment of exfoliated abrasive grains while grinding, in a grinding method for forming a ring-shaped reinforcement part on the reverse face of the workpiece.SOLUTION: A method of grinding the reverse face Wb of a workpiece W, having a device region Wa1 and an outer boundary excessive region Wa2 on the surface Wa, with a grind stone 42b includes a protective step of covering the surface Wa of the workpiece W with a protective member T1, a step of holding the protective member T1 side by the holding surface 30a of a table 30 rotating by a revolving shaft 33 inclining at an angle of 45-180 degrees for the vertical direction after execution of the protective step, and a grinding step of grinding the workpiece reverse face Wb, corresponding to the device region Wa1 with the grind stone 42b rotating by a revolving shaft 40 orthogonal to the holding surface 30a, while supplying the grinding water, thus forming a circular recess Wb1 and a ring-shaped reinforcement part Wb2 surrounding the circular recess Wb1. In the grinding step, draining of the grinding water containing the exfoliated abrasive grains is accelerated by gradient of the workpiece W.SELECTED DRAWING: Figure 4 【課題】被加工物の裏面にリング状補強部を形成する研削方法において、研削中の脱落砥粒の巻き込みを要因とする裏面に対するスクラッチの形成や被加工物の割れの発生を防ぐ。【解決手段】デバイス領域Ｗａ１と外周余剰領域Ｗａ２とを表面Ｗａに有する被加工物Ｗの裏面Ｗｂを砥石４２ｂで研削する方法であり、被加工物Ｗの表面Ｗａを保護部材Ｔ１で覆う保護ステップと、保護ステップ実施後、鉛直方向に対し４５度〜１８０度の角度に傾斜した回転軸３３で回転するテーブル３０の保持面３０ａで保護部材Ｔ１側を保持するステップと、保持面３０ａと直交する回転軸４０で回転する砥石４２ｂでデバイス領域Ｗａ１に対応する被加工物裏面Ｗｂを、研削水を供給しつつ研削し円形凹部Ｗｂ１と円形凹部Ｗｂ１を囲むリング状補強部Ｗｂ２とを形成する研削ステップ、を備え、研削ステップでは、脱落砥粒を含む研削水の排出が被加工物Ｗの傾斜により促される研削方法である。【選択図】図４