Semiconductor-based radiation image detector and its manufacturing method

Claim 1

A radiation image detector for detecting a radiation image with the image divided into pixels, comprising: a radiation-sensitive semiconductor plate (1); a common bias electrode (2) deposited on one surface of the semiconductor plate; a plurality of pixel-corresponding signal takeout electrodes (3) deposited on the other surface of the semiconductor plate; a plurality of bumps (4) each of which is fixed on a respective one of the signal takeout electrodes; a passivation film (7) covering each signal takeout electrode where not in contact with its bump, and covering the clearances between the signal takeout electrodes; and a base plate (5) on which are provided a plurality of pads (6) corresponding to the bumps.

Claim 6

A method of manufacturing a radiation image detector for detecting a radiation image with' the image divided into pixels, the method comprising: a first step of plating a semiconductor plate (1) on its one surface with a common bias electrode (2); a second step of plating said semiconductor plate (1) on its other surface with a plurality of pixel-corresponding signal takeout electrodes (3); a third step of depositing a passivation film (7) covering the signal takeout electrodes except for a portion of each, and covering clearances left among the signal takeout electrodes; a fourth step of providing metal protrusions (4a,4) on the uncovered portions of signal takeout electrodes.

Claim 7

A method of manufacturing a radiation image detector for detecting a radiation image with' the image divided into pixels, the method comprising: a first step of plating a semiconductor plate (1) on its one surface with a common bias electrode (2); a second step of plating said semiconductor plate (1) on its other surface with a plurality of pixel-corresponding signal takeout electrodes (3); a third step of depositing a passivation film (7) covering the signal takeout electrodes except for a portion of each, and covering clearances left among the signal takeout electrodes; a fourth step of providing metal protrusions (4a,4) on the uncovered portions of signal takeout electrodes.

Claim 9

A method of manufacturing a radiation image detector for detecting a radiation image with the image divided into pixels, the method comprising: a first step of plating a semiconductor plate (1) on its one surface with a common bias electrode (2); a second step of plating said semiconductor plate (1) on its other surface with a plurality of pixel-corresponding signal takeout electrodes (3) incorporating a process of laying, in advance, a first photoresist film (11) so as to define positions to be plated with the signal takeout electrodes, the first photoresist film being removed after the positions are plated with the signal takeout electrodes; a third step of laying second photoresist films (11a) respectively on the respective central portions of the signal takeout electrodes by employing a photomasking technique; a fourth step of depositing a passivation film (7) of silicon oxide covering the signal takeout electrodes, the second photoresist films and clearances left among the signal takeout electrodes; a fifth step of removing the second photoresist films together with parts of said passivation film deposited on the second photoresist films; a sixth step of laying, by employing photomasking technique, a third photoresist film (1lb) on parts of the passivation film remaining after the fifth step; a seventh step of depositing a metal layer (8a) on all the surface formed by the sixth step, the metal layer having recessed portions corresponding to the respective central portions of the signal takeout electrodes; an eighth step of laying, by employing a photomasking technique, a fourth photoresist film (11c) on the metal layer except for the recessed portions; a ninth step of providing solder metal protrusions (4a) at the recessed portions by means of electroplating with the metal layer used as an electrode; a tenth step of removing the fourth and the third photoresist films (11c, 11b) together with parts of the metal layer deposited on the third photoresist film; an eleventh step of melting the solder protrusions so as to form solder beads (4); and a twelfth step of soldering, by means of a flip-chip joining technique, the solder beads to pads fixedly provided on a separately prepared base plate, the pads being arrayed corresponding to the solder beads.

Claim 10

A method of manufacturing a radiation image detector for detecting a radiation image with the image divided into pixels, the method comprising: a first step of plating a semiconductor plate (1) on its one surface with a common bias electrode (2); a second step of plating said semiconductor plate (1) on its other surface with a plurality of pixel-corresponding signal takeout electrodes (3) incorporating a process of laying, in advance, a first photoresist film (11) so as to define positions to be plated with the signal takeout electrodes, the first photoresist film being removed after the positions are plated with the signal takeout electrodes; a third step of laying second photoresist films (11a) respectively on the respective central portions of the signal takeout electrodes by employing a photomasking technique; a fourth step of depositing a passivation film (7) of silicon oxide covering the signal takeout electrodes, the second photoresist films and clearances left among the signal takeout electrodes; a fifth step of removing the second photoresist films together with parts of said passivation film deposited on the second photoresist films; a sixth step of laying, by employing photomasking technique, a third photoresist film (1lb) on parts of the passivation film remaining after the fifth step; a seventh step of depositing a metal layer (8a) on all the surface formed by the sixth step, the metal layer having recessed portions corresponding to the respective central portions of the signal takeout electrodes; an eighth step of laying, by employing a photomasking technique, a fourth photoresist film (11c) on the metal layer except for the recessed portions; a ninth step of providing solder metal protrusions (4a) at the recessed portions by means of electroplating with the metal layer used as an electrode; a tenth step of removing the fourth and the third photoresist films (11c, 11b) together with parts of the metal layer deposited on the third photoresist film; an eleventh step of melting the solder protrusions so as to form solder beads (4); and a twelfth step of soldering, by means of a flip-chip joining technique, the solder beads to pads fixedly provided on a separately prepared base plate, the pads being arrayed corresponding to the solder beads.